Assertion and Reason. Alkali metals. s and p-block Elements 809

Transcription

1 s and p-blck Elements 809 Assertin and Reasn 1 b b a a 5 a 6 c 7 b 8 e 9 a 10 a 11 e 1 a 1 a 1 a 15 a 16 c 17 b 18 c 19 d 0 d 1 a b d d 5 b 6 d 7 c 8 c 9 a 0 a 1 a c b a 5 a 6 b 7 a 8 b 9 b 0 b 1 a c a d 5 c 6 a 7 d 8 b 9 d 50 a 51 e 5 b 5 d 5 b 55 c 56 a 57 a 58 a 59 d 60 b 61 a 6 b 6 c 6 b Alkali metals 1 (b) Element Na K IE IE Sdium has higher IE because f smaller atmic size (c) Alkali metals are highly reactive metals They react with Alchl C 5 K C 5K Water K K ( Ammniated ) x catin Ammnia K x y) N K( N [ e( N ) y ] Ammniated electrn But they d nt react with kersene (b) After remval f an electrn the effective nuclear charge per electrn increases hence the size decreases 5 (a) Alkali metals valence shell cnfiguratin ns 6 (b) Element Li Na K Rb Cs Inic radius (pm) as the atmic n increases the n f shells increases hence, atmic radius increases 7 (c) n mving dwn the grup electrpsitive character increases 8 (a) Carnellite KCl MgCl 6 Crylite Na Al6 Bauxite ( Al ) Dlmite MgC CaC 10 (d) Element Li Na K Rb Atmic radius (pm) (b) Li is much sfter than the ther grup I metals Actually Li is harder then ther alkali metals 1 (a) Cu e Cu, E 0 V Mg e Mg, E 7 V Na e Na, E 71 V 1 (d) Anhydrus frm f Na C des nt decmpse n heating even t redness It is a amrphus pwder called sda ash 17 (c) ehling's slutin is a mixture f Alk CuS Na K tartarate (Rchelle salt) 19 (b) K Cl KCl (vilent reactin) 0 (b) Althugh lattice energy f LiCl higher than NaCl but LiCl is cvalent in nature and NaCl inic there after, the melting pint decreases as we mve NaCl because the lattice energy decreases as a size f alkali metal atm increases (lattice energy melting pint f alkali metal halide) (b) It frm calcium and magnesium cmplex with EDTA salt (a) Li < Na < K < Rb Dwn the grup basic character increases 5 (d) Na C 10 NaC washing pwder Na C 6 (b) Na C, KC and ( N ) C are sluble in water because hydratin energy is mre than lattice energy 9 (c) KS Al( S ) ptash alum it is a duble salt 1 (d) It is a clurless gas (a) NaC (Salt f strng base & weak acid) Na C C (b) es ( N ) S 6 Mhr s salt 5 (d) Ca Na Mg Al 6 (b) Li e Li, E 05 V K e K, E 9 V Ca e Ca, E 87 V 7 (a) Because their valence electrns are present in s- rbitals 8 (a) 6Li N Li N Lithium nitride 9 (d) Li, Na, K are lighter than water but Rb is heavier than water (c) K K K (b) Cs Rb K Na Li Metallic character decreasing rder 5 (d) Rb Rb Li Na K Rb Cs As we g dwn the grup reactivity with 8 (b) Atmic number 11 Na Na Na Na (base ) increases 51 (d) Generally inic character decreasing frm LiCl t NaCl 5 (c) In castner prcess Na metal is made f ande 55 (a) ajan s rule is applied

2 810 s and p-blck Elements 57 (a) Small atmic and inic size leads t high electrnegativity and hydratin energy Small atmic and inic size leads t high electrnegativity and hydratin energy 58 (c) Mhr salt is ( es )( N ) S 6 60 (a) Sdium thisulphate is a reducing agent which cnvert metalic silver int silver salt 6 (a) In alkali metal grup elements alkali means plant ash heat 67 (d) Na N NaN 1 mist air 68 (a,b) Na Na Na Na 69 (d) KCl KCl 70 (d) Due t free electrn liquid ammnia becmes paramagnetic 7 (a) They pssess highest atmic vlume in their respective perids 7 (c) e () is sluble in sdium hydrxide slutin 76 (d) The cell invlves the fllwing reactin, NaCl Na Cl At ande : Cl Cl e Cl At cathde : Na Na g amalgam At ande : e Na Na amalgam Na g e At cathde : e 78 (a) Li is a mre reducing agent cmpare t ther element 79 (b) Element Li Na K Rb Cs Mpt in K (a) Na Na K K 8 (a) Alkali metal are gd cnductr f heat and electricity 8 (c) tassium react with halgens (chlrine) t gives vilet clur flame 8 (b) Mbility decreases frm tp t bttm because f the atmic size is increases 85 (c) Lithium shws dignal relatinships with Mg 86 (c) K Ca C Cl Electrpsitive character in decreasing rder 87 (d) Mlten Electrlysis NaCl Na Cl Cathde Ande 88 (b) When sdium bicarbnate ( NaC ) is heated, sdium carbnate, C and water are frmed NaC NaC C Sdium carbnate 89 (c) Alum is used fr sftning f water 90 (a) nly salts f (weak acid + strng base) and (strng acid + weak base) get hydrlysed (ie, shw alkalinity r acidity in water) KCl is a salt f strng acid and strng base therefre it des nt get hydrlysed in water KCl K Cl ; + K Strng Cl Strng 91 (c) Carbn dixide des nt help in burning, als it frms carbnate with alkali metals 9 (a) When carbnate are heated they decmpse t frm the xide Sdium carbnate and ptassium carbnate d nt decmpse The carbnate becme mre difficult t decmpse as we g dwn the grup 9 (c) Aluminium reacts with caustic sda t frm sdium meta aluminate Al Na NaAl Sdium meta aluminate 9 (a) Alkaline earth metals ( ns ) are denser than alkali metal 1 ( ns ) because metallic bnding in alkaline earth metal is strnger 95 (c) Lithium is basic in nature and hence it is nt amphteric 96 (a) Cs f the fllwing is mst basic in character due t increase electrpsitive character in a grup f alkali 97 (a) Grup I element are s highly electrpsitive that they emit electrns even when expsed t light (htelectric effect) and this character increase n mving dwn the grup frm lithium twards cesium 98 (b) Lithium frm nitride n heating with nitrgen Lithium nitride gives ammnia when heated with Ammnia gas frm tetrammine cpper cmplex with CuS slutin 6Li N Li N Li N CuS Li N N [ Cu( N ) ] S 99 (d) The given cmpund x must be CaC It can be explained by fllwing reactins, CaC Ca C ; Ca Ca( (x) Residue Ca( ) C C Ca( ) z Ca ( C ) CaC C (x) ) (y) 100 (c) Accrding t ajan's rule RbCl has greatest inic character due t large inic size f Rb in BeCl has least inic (Maximum cvalent) due t small size f plarising 105 (c) Na N NaN 110 (d) Na Na 11 (c) It reacts with alchl t frm sdium alkxide C C Na 5 Na 5 Be in which has highly 11 (a) Causticizing prcess (Gssage prcess) it is an ld prcess and invlves heating f 10% slutin f Na C with a little excess f milk f lime Ca () Na C Ca ) CaC Na ( C 11 (c) Na C CNa 510 atm 115 (a) NaCl Na Cl 119 (b) Na is a deliquescent white crystalline slid It absrbs misture frm the atmsphere 10 (a) Na C S NaS C 1 (c) Ca Na is called sda lime : 1 1 (c) Mlten sdium is used as a clant

3 s and p-blck Elements (c) AgBr Na S Na [ Ag( S ) ] NaBr 18 (b) 19 (a,b) Na S S Na NaS Sd thisulphate NaCl Na Cl Ande Cathde 1 (b) Sn Na NaSn Electrlysis 15 (b) NaCl Na Cl 16 (d) Electriccurrent NaCl Na Cl Catin Anin Ande 18 (a) gcl Na g NaCl 19 (a) Dwn s cell is used fr the electrlysis f fused NaCl 1 (c) e() des nt disslve in Na Cathde 1 (a) Castner s prcess used t btain Na, by electrlysis f sdium hydrxide 1 (a) Excess f Na in causes high B 15 (b) erric alum is ( N ) S e( S) 16 (d) When Na is heated in presence f air r xygen, Na burns t frm sdium xide and sdium perxide 18 (d) yrlusite r Manganese dixide ( Mn ) is a mineral f manganese 19 (c) CaCl bring dwn the melt temperature frm 1075 K t 850 K Alkaline earth metals 1 (d) CaS r ( CaS ) (a) CaCl because it is hygrscpic 7 (d) Setting f plaster f paris is exthermic prcess 1 CaS CaS rthrhmb ic ardening CaS The setting is due t frmatin f anther hydrate eat Mn rthrhmb ic Gypsum 10 (a) MgC Mg C The metal whse xide is stable, it's carbnate is unstable 1 (d) (Mlten) Electrlysis MgCl Mg Ande Catin Cl Anin Cl Cl e, Cl Cl Cl Cathde Mg e Mg 1 (a) Because f small atmic size and high IE Be frms cvalent chlride 16 (d) BeS is mst sluble because hydratin energy is mre than lattice energy BeS > MgS > CaS > SrS > BaS ydratin energy decreases hence, slubility decreases Gypsum Dehydratin laster f paris 10 C 19 (b) ( CaS ) CaS 1 (b) Lithpne ZnS BaS ) is used as a white pigment ( (d) Ca( ) Cl CaCl Slaked lime Bleaching pwder (a) Strntium Crimsn r pink clur 6 (b,c) Ca 6Ca( ) 7 (d) K CaCl Cathde : K Ca Cl Cathde Ande Ca e Ca Ande : Cl e Cl 8 (d) Element Mg Al Si Atmic radii (Å) as we mve acrss the perid nuclear charge increases, hence, size decreases 0 (b) MgCl 6 5Mg x MgCl 5Mg x Magnesia cement r srrel cement 1 (d) ZnS BaS is lithpne used as white pigment 6 (d) Aqueus CaCl r hydrated CaCl can nt act as dehydrating agent 8 (d) As we g dwn the grup electrpsitive character increases because IE decreases Ba is mst electrpsitive element in the grup 9 (d) Due t the inert pair effect 0 (a) Element Be Al Electrnegativity (c) Be Mg Ca Sr Ba n mving dwn the grup lattice energy remains almst cnstant as the sulphate is s big that small increase in the size f the catins frm Be t Ba des nt make any difference wever the hydratin energy decreases frm Be t Ba This causes decrease in the slubility f the sulphates as the inic size increases (a) Element Be Mg Ca Sr Ba Electrde ptential (a) Element Mg Ca Sr Ba IE (a) Be due t diagnal relatinship 5 (a) K is highly sluble because f high hydratin energy 7 (b) Mg Al Si 5 Basic Mg Mg( Base r alkali ) 8 (d) Duralium ( Al 95%, Cu %, Mn 05%, Mg 05%) being light, tugh and durable is used fr the manufacture f aerplanes and autmbile parts 9 (c) Na K Ba Ca Sr Yellw Amphteric ale vilet Apple green Brick red Crimsn 51 (a) Magnesium burns with an intense light Therefre Mg is used in flash bulbs fr phtgraphy, firewrks and signal fires 5 (b) Ca C CaC Ca Ca( ) Acidic 5 (a) When water is added t cement an exthermic reactin ccurs During this prcess, the cement reacts with water t frm a gelatinus mass which slwly sets int a hard mass having three dimensinal netwrk structure invlving Si Si and Si Al chains

4 81 s and p-blck Elements 55 (b) Ca (quick lime) Ca () (slaked lime) Ca( ) an aqueus suspensin f Ca () in water is called lime water CaC (lime stne) 57 (d) Lime stne CaC Clay silica and alumina Gypsum CaS 59 (b) Because hydratin energy decreases dwn the grup 6 (d) Be des nt react with water 6 (a) (i) Small atmic size (ii) igh electrnegativity (iii) Absence f d rbitals 65 (a) Ba( ) Sr( ) Ca( ) Mg( ) Slubility decreasing rder 66 (d) Slubility increasing tp t bttm 67 (a) Be t Ba inic character increasing 70 (a) Ca Ca( ) Ca Ca( ) 7 (a) They are denser than alkali metals because they can be packed mre tightly t their greater charge and smaller radii 76 (d) Be( ) Mg( ) Ca( ) Sr( ) Ba( ) n mving dwn the grup basic character increases 77 (b) Mg () Mg is mst electrpsitive element amngst the given elements 78 (d) Lime stne = CaC Quick lime = Ca Slaked lime = Ca () 79 (c) As we g dwn the grup IE decreases ence, Ba can easily give electrns Therefre strngest reducing agent 80 (c) 1 1 CaS CaS ard mass laster f paris 8 (a) BeCl MgCl CaCl BaCl As we g dwn the grup IE decreases ence inic character increases heat 8 (c) MgCl 6 Mg 5 Cl 8 (a) The slubility f hydrxides f alkaline earth metals in water increases n mving dwn the grup 85 (c) Bleaching actin f Cl in mist cnditin is permanent Cl + Cl + Cl Cl Cl + Cl + Cl + Clured matter + nascent xygen clurless matter 86 (d) The slubility f hydrxides f alkaline earth metals in water increases n mving dwn the grup 87 (c) C escapes simultaneusly 88 (d) It cnsist f high lattice energy and lwest hydratin energy 90 (a) It is a s-blck elements 91 (b) Barium Ba 56 is a alkali earth metal 9 (c) Thermal stability increasing frm tp t bttm 9 (b) n mving dwn the grup; Lattice energy decreases with increase in size f catin 96 (d) BaS is sparingly sluble in water because the slubility f secnd grup sulphates decreases with increasing atmic size Because f hydratin energy decreases 97 (d) Berylium because f small atmic size and high inizatin energy 99 (a) Mg Ca Sr Ba Ra Inic nature increases as we g dwn the grup inic nature increases because IE decreases 100 (b) CaS Gypsum 1 CaS laster f paris (b) Ca Ca 10 (c) Calcium cyanamide is the slw acting nitrgenus fertilizer as it decmpse very slwly CaNCN CaC N CN N Urea CN C N Nitrifying N Slublenitrates lants bacteria 10 (a) laster f paris [( CaS ) ] is used in surgery fr setting f bnes, dentistry and manufacturing f statues It is prepared as fllws, 15 C CaS ( CaS ) laster f paris 10 (b) Due t electrpsitive and reactive in nature, magnesium is readily cnverted int psitive ins n cntact with irn pipes and hence, irn pipes remains as it is 105 (c) A binary cmpund is ne made f tw different elements These can be ne f each element such as CuCl r e These can als be several f each element such as e r SnBr Metal which have variable xidatin number can frm mre than ne type f binary cmpund like e shws the xidatin state + and + ence it frms tw type f binary cmpund eg, ecl, ecl 106 (a) Diagnal relatinship: elements f nd perid ften shw resemblance t the element f the IIIrd perid diagnaly placed t it This type f behaviur is called as diagnal relatinship Li shws the diagnal relatinship with Mg 107 (a) MgCl NaC Mg( C ) ( aq) NaCl Mg ( C ) ( aq) MgC C 108 (c) We knw that eat (White ppt) MgCl 6 MgCl 6 Thus in this reactin magnesium dichlride is prduced 109 (d) Magnesium burns in C t prduce Mg C Mg C 110 (d) Srel's cement is, MgCl 5Mg x 111 (b) Clemnite is a mineral f brn having cmpsitin as CaB611 5

5 s and p-blck Elements 81 Brn family (a) B C Cl BCl C BCl is btained by passing chlrine ver the heated mixture f B and pwdered charcal 6 (d) B 6 has tw types f B bnds B 119 pm B B (Terminal bnd) B 1 pm (Bridge bnd) 1 (b) Dilthey in 191 prpsed a bridge structure fr dibrane ur hydrgen atms, tw n the left and tw n the right, knwn as terminal hydrgens and tw brn atms lie in the same plane Tw hydrgen atms frming bridges, ne abve and ther belw, lie in a plane perpendicular t the rest f mlecule 15 (c) B B 177 Å 16 (a,c,d) Al Cl 6, InCl 6, GaCl 6 17 (a) Liquified Ga expand n slidificatin Ga is less electrpsitive in nature, It has the weak metallic bnd s it expand n slidificatin 18 (d) AlCl6 1 [ Al( ) ] 6Cl 19 (e) B C is the hardest substance alng with diamnd 0 (a) Brazine B N6, is iselectrnic t benzene and hence, is called inrganic benzene sme physical prperties f benzene and brazine are als similar N B Å B N B 1 Å N B 1 (c) Except B Brazine () all ther hydrxide are f Benzene metallic hydrxide having the basic nature B () are the hydrxide f nnmetal shwing the acidic nature (c) Missan brn is amrphus brn, btained by reductin f B with Na r Mg It has 95-98% brn and is black in clur 6 97 C C B C C 1 C C (d) Brn frm different hydride f general frmula Bn n and Bn n6 but B is unknwn (c) Alumina is amphteric xide, which reacts acid as well as base 5 (a) Al is the mst abundant metal in the earth crust 9 (a) AlCl 6 Al( ) Cl Thus AlCl can nt be btained by this methd 0 (d) Amphteric substance can react with bth acid and base (c) Al 6Cl AlCl (c) Al III grup rms Al 5 (d) K Al KAl 7 (c) NaC Na C Na Al 6 1 (c) B( ) B Bric acid Al ( ) Amphteric Na[ Al( ) ] 5 (b) es ( N ) S 6 6 (b) Al is an amphteric xide 7 (c) Aluminium xide is highly stable therefre, it is nt Reduced by chemical reactins 8 (d) Aluminium is used as reducing agent in metallurgy 9 (a) Al is used as reducing agent in thermite prcess 50 (c) In Gldschmidt aluminthermic prcess, thermite cntains parts f e and 1 part f Al 51 (c) r the purificatin f red bauxite which cntains irn xide as impurity Baeyer s prcess r the purificatin f white bauxite which cntains silica as the main impurity Serpeck s prcess 5 (b) In all s prcess Al NaC NaAl C NaAl C Al( Na C ) 17 K K Al( ) Al 5 (d) Crylite Na Al6 (1) Decreases the melting pint f alumina () Increases cnductivity f the slutin 55 (b) Crylite Na Al6 is added (1) T decrease the melting temp frm K t 110 K () T increase the electrical cnductivity f slutin 61 (d) Irn xide impurity Baeyer s prcess Silica impurity Serpeck s prcess 6 (b) Crylite is added t lwer the melting pint f alumina and t increase the electrical cnductivity 65 (c) The purificatin f alumina can be dne by Baeyer s prcess 67 (c) In electrlytic methd f btaining aluminium frm purified bauxite, crylite is added t charge because it reduces the melting pint f Bauxite (frm 100 C t C ) and als it increases electrical cnductivity f mixture 68 (a) p s prcess urificatin f Al all and erult prcess Reductin f Al Baeyer s and Serpeck s prcess Cncentratin f Bauxite re 7 (a) B B c e : B B ; c e : B

6 81 s and p-blck Elements 75 (a) B 6 76 (b) ure alumina is a bad cnductr f electricity and the fusin temperature f pure alumina is abut 000 C and at this temperature when the electrlysis is carried f fused mass the metal frmed vapureses as the biling pint f Al is 1800 C T vercme this difficulty, Na Al6 and Ca are mixed with alumina 77 (a) Cncentratin f Lewis acid f brn tri halides is increased in fllwing rder B BCl BBr BI Carbn family (d) It react with alkali as well as acid 6 (a) Amng alkali metal carbnates nly Li C decmpses Li C Li C 7 (b) rpyne can be prepared by the hydrlysis f magnesium carbide + CC C + MgC Mg() 10 (d) Generally red lead decmpse int b and 11 (c) C is acidic xide and thus mre effectively absrbed by an alkali 1 (b) CaC have ne sigma and tw bnd 1 (d) C and Si are nn-metal and b is a metal 16 (a) Si Mg Si Mg 17 (b) Generally IV grup element shws catenatin tendency and carbn has mre catenatin pwer 18 (b) Metal xides r sme salts are fused with glass t imprted clur f glass 19 (d) Al (C ) is less sluble in water than Na C, ZnC 0 (d) The inert pair effect is mst prminent in b because frm tp t bttm due t increase in number f shells 5 (c) 00 C C Na CNa Sd frmate 7 (c) Sdium xalate react with cnc S t frm C and C gas (d) It is hydrlysed with water t frm a Si () 5 (b) When hydrgen perxide react with bs then they frm bs 6 (b) Grey tin is very brittle and easily crumbles dwn t a pwder in very cld climates Grey tin (Tetragnal) (Cubic) B B Empty sp rbital f B Empty sp rbital f B The change f white tin t grey tin is accmpanied by increase in vlume This is called tin disease r tin plague 7 (c) Slid C is knws as dry ice because it evaprates at 78 C withut changing in the liquid state 8 (b) Zelite have Si and Al tetrahedrns linked tgether in a three dimensinal pen structure in which fur r six membered ring predminate Due t pen chain structure they have cavities and can take up water and ther small mlecules 9 (b) Crk's glass is a special type f glass cntaining cerium xide It des nt allw the passage f ultra vilet ray and is used fr making lenses 0 (b) Inert pair effect becme significant fr the 6th and 7th perid f p-blck element 1 (a) Carbn subxide has linear structure with C C bnd length equal t 10 Å and C bnd length equal t 10 Å C C C C C C (c) b is a mixed xide It can be represented as b b (b) Nble gases are fund in very minute amunt in atmsphere These are separated frm each ther by using ccnut charcal Which adsrb different gas at different temperature (c) Lapis Lazuli is a rck cmpsed mainly f the fllwing mineral, lazurite, hauynite sdalite, nsean, calcite, pyrite, lapis lazuli is actually sulphur cntaining, sdium aluminium silicate having chemical cmpsitin Na Al6Si NaS 5 (d) In carbn family stability + xidatin state increases n mving dwn the grup in the peridic table with an increase in atmic number due t screening effect 6 (c) Tin is xidised t meta stannic acid when it is treated with nitric acid Sn N Sn N 7 (c) b Sn 9 (d) Three dimensinal sheet structures are frmed when three xygen atms f each [Si] tetrahedral are shared 50 (a) b Red lead (Sindhur) 51 (c) White lead bc b( ) 5 (c) rganic acids disslve lead in presence f xygen 1 b C C b( C C) 5 (a) Si Si 55 (a) S Ttal valence electrns IV grup 56 (c) bcl is mst inic because n ging dwn the grup the metallic character increases and als the inert pair effect predminates 58 (b) Type metal b = 8%, Sb = 15%, Sn = % 60 (b) Sugar f lead ( C C) b lead acetate 6 (d) b 11 g/ml eaviest 6 (c) b is a mixed xide f b b 67 (c) Brn (B), Si, Ge, As, Sb, and At are the metallid elements Bismuth (Bi) and tin (Sn) are metals while carbn (C) is nnmetal 68 (a) Al C 1 C Al( ) 69 (b) Glass being a mixture f sdium and calcium silicates reacts with hydrfluric acid frming sdium and calcium flursilicates respectively NaSi NaSi CaSi CaSi The etching f glass is based n these reactins Nitrgen family

7 s and p-blck Elements 815 (b) es N es N (Brwn) (b), metaphsphric acid 6 (a) White phsphrus is sluble in CS whereas red phsphrus is insluble in it 7 (d) 7 pyrphsphric acid Tetrabasic ( grups) 8 (b) Na (White) Na hsphine Sd hypphsph ite 9 (a) NCl 5 is nt knwn because f absence f d-rbitals in nitrgen 11 (a,d) mlecule 1 (b) N Bnd angle 60 Six = Single bnds Lne pairs = N N ( S ) Nitrus xide (Laughinggas) 1 (a) Birkeland Eyde prcess Dinitrgen is prepared cmmercially frm air by liquificatin and fractinal distillatin When liquid air is allwed t distil, dinitrgen having lwer bpt (77K) distils ver first leaving behind liquid xygen (bpt 90K) Wrld wide prductin f dinitrgen frm liquid air is mre than 50 millin tnns per year 1 (b) N N N NaN ( s) ( s) NaN ( s) Lunar caustic AgN ( s) Ag( s) N ( g) ( g) b( N) b N ( s) 16 (b) Na Na White hsphine 17 (d) N As Sb Bi 18 (b) - grups are present hence it is tribasic 19 (c) Nitrus acid behaves as reducing as well as an xidising agent It reduces ptassium permanganate, ptassium dichrmate, and ther strng xidising agents It xidises strng reducing agents such as hydridic acid, sulphurus acid etc It xidises 60 e int Nn-metals Metallids Metal e in acidic medium; e N e N It reduces acidified KMn KMn S 5N 0 (a) KN KN (b) ( S ) K S MnS 5 ( S ) N Cl KN N N KCl N (d) N N5 Nitric acid N 1770K Ca (c) ( ) Si 6CaSi K White 10C 10C 6 (c) (c) 8 (c) (i) (iv) Nitric xide Clurless gas N (ii) N Dinitrgen (v) tetraxide clurless liquid Nitrus xide Clurless gas N (iii) N 5 Dinitrgen pentaxide clurless gas N Dinitrgen liquid trixide Blue 0 (c) ( N ) Cr 7 Cr N 1 (d) N N (c) Because f its very lw ignitin temperature (0K) it is always kept under water (d) N when disslved in water frms N N N (a,b) Stability f + xidatin states increases n accunt f inert pair effect Reducing character f hydrides increases dwn the grup because bnd dissciatin energy decreases dwn the grup 5 (a) aber s prcess Industrial prcess e - M N N atm K 6 (a) 5 10 ; white phsphrus gets easily xidized because it is highly reactive 8 (d) N is itself nn-cmbustible but supprts cmbustin S N N S 9 (b) When N is inhaled in mderate quantities, it prduces hysterical laughter, hence the name laughing gas 0 (c) N N N When disslved in water, gives a mixture f nitrus acid and nitric acid N N N N N Na NaN NaN 1 (b) Zn 10N Zn( N ) 5 N ht & dil

8 816 s and p-blck Elements (a) ( ) n lymetaphsphric acid (b) Superphsphate f lime It is a mixture f calcium dihydrgen phsphate and gypsum and is btained by treating phsphatic rck will cnc S Ca( ) S 5 Ca( ) CaS Superphsp hate f lime (d) Na Na t K 6 (d) N 5 N N is used in the preparatin f N N N ; N N 7 (d) 0N 0N 9 (b) A B Bi Acidic xides Alkaline 50 (b) 51 (a) N N It is least basic because f the high electrnegativity f atms The lne pair present n nitrgen atm is nt easily available fr dnatin 5 (d) Cl Cl 5 (c) Due t less reactivity f red phsphrus 5 (d) N brwn clured gas 55 (d) N 5 is an anhydride f N 56 (c) 57 (b) 58 (c) N N 5 Therefre, it can act nly as xidising agent * * N N N N (xidatin number ) 1 1 x x x x 1 * 8 x ( 8) 0 x x * N x ( ) 1 0 x 1 0 x 1 60 (c) N As Sb n mving dwn the grup atmic size increases and availability f lne pair decreases ence, basic character decreases 61 (a) As Sb Bi n mving dwn the grup bnd energy decreases ence, stability decreases 6 (d) Due t absence f d-rbitals in N atm, it cannt accept electrns frm fr hydrlysis f N 6 (b) N is mst thermally stable hydride ence, electrlysis temperature is maximum 6 (a) hsphrus is kept in water due t it burt at 0 C 66 (c) BiCl BiCl Cl 67 (c) When the black ppt f Bi S is disslved in 50% N and a slutin f N is added A white ppt f Bi () is btained 69 (a) Atmspheric nitrgen is inert and unreactive because f very high bnd energy ( 95kJ / mle) 70 (b) Bismuth des nt shw alltrpy ther elements shw alltrpy Nitrgen -nitrgen and -nitrgen (slid crystalline frms) hsphrus White, Red and Black frms Arsenic Yellw and Grey frms Antimny Yellw and Grey frms 71 (a) Nitrgen des nt frm cmplexes because f the absence f d- rbitals 7 (a) N is a strngest base because Lne pair is easily available fr dnatin 7 (b) ydride N As Sb Bi Bling pint (a) NCl is highly reactive and unstable ence it is explsive 76 (b) N As Sb Bi Acidic character decreases dwn the grup 77 (c) SbCl is nt exists because Vth grup elements nrmally shw + and +5 xidatin state 78 (b) N Cl NaN N N NaCl ( aq ) N ( aq) heat N N ( g) ( l) 79 (c) N N N 80 (d) 6Li N Li N Lithium nitride Mg N Mg N Magnesium nitride 81 (d) N N bnd energy is very high 8 (d) 85 (d) 7 s, s, N 1 p d-rbitals are absent in nitrgen N heat N N (Laughing gas) kJ ml 86 (d) N N N 87 (c) N is a linear mlecule 88 (b) N N 89 (d) N N 5 Acidic xides Amphteric Basic 90 (c) b( N) b N 91 (a) b( N) b N 9 (b) Cu 8N Cu( N ) N 9 (d) In upper atmsphere N is frmed by lightning flash

9 s and p-blck Elements 817 N N 96 (c) N N 98 (b) AgN AgN AgN 100 (d) N N N C 101 (d) cnc N C1 11 C xalic acid t C 10 (b) N 5 N 10 (d) N can be either reduced t nitric xide (N) r xidised t nitric acid and hence it acts bth as an xidising as well as a reducing agent N N [ ] N ] [ N 106 (d) N is highly vlatile cmpund When vapurized, liquid ammnia causes intense cling ence used as a clant in ice factries and cld strages 107 (d) N ydrazic acid N 108 (a) d-rbitals are absent in nitrgen 109 (d) hsphide in Chlride in ( ) ( Cl ) Ttal electrns and Cl are iselectrnic 110 (a) Due t the less reactivity 116 (a) Na Na hsphine Sd hypphsph ite 117 (c) Bth xidatin and reductin (Disprprtinatin) 0 Na 118 (b) Na N reactin Red 1 Na 10 (c) Ca 6 Ca( ) 1 (b) is less basic because lne pair is nt easily available fr dnatin 1 (d) 1 (d) 5 rthphsphric acid 15 (c) Mnbasic acid nly ne grup 16 (b) Cl Cl 17 (b) 18 (c) Reductin * x ( ) 0 x 1 xidatin 19 (d) Na 7 Salt f strng acid and strng base 10 (b) 6 S 6S 11 (c) CaCN CaC N 1 (b) 7 Tetrabasic grup are present 1 (b) BiCl BiCl Cl C 15 (b) CaC N CaCN C 68 atm 16 (a) CaCN CaC N 17 (a) N CN Mass f N % f N = 100 Mass f cmpund 11 (a) Anhydride f nitrus acid is N 8 = 100 = 6% 60 1 (b) Na Na 15 (a) N is highly sluble due t -bnding N 16 (d) N As Sb Bpt in (K) (a) * x 1 0 x 151 (d) Slid Cl 5 exists as 15 (a) -bnding 60 Cl and Cl 6 15 (e) hsphrus minerals is called as hydrxy apatite and flurapatite 156 (a) Nitrgen des nt have d-rbitals 157 (c) Cu N Cu N 159 (b) Liquid ammnia is used in refrigeratin because it has high heat f vaprisatin 160 (a) Sn cnc N Sn N Meta stannic acid 161 (c) Cu 8N Cu ( N N ) Nitric xide 16 (c) entavalency in phsphrus is mre stable that f nitrgen due t large size f phsphrus atm 16 (b) Ammmium nitrate is neutral fertilizer 165 (d) insluble in water because des nt cnsist f hydrgen bnd

10 818 s and p-blck Elements 166 (a) N Cl NaN N N N N N 167 (a) Nitrgen react with metal t frm a nitride 168 (a) 50 C 6Li N Li N (Lithium nitride) : : : :: (b) It is a salt f pyrphsphric acid 7 17 (d) Cpper react with cnc nitric acid t frm a nitric xide 17 (a) N n accunt f stimulating effect n nervus system 17 (d) Sdium metal in liq N slutin shws strng reducing pwer due t slvated electrn Na ( x y) N [ Na ( N 175 (c) Cl Cl Cl 5 ) ] x [ e( N ) y ] slvated electrn 178 (c) Generally 5 are used as a dehydrating agent 180 (a) hsphrus shw + 5 valency 181 (b) In the aber prcess fr the manufacture f N, e is used catalyst and M as a prmtre 18 (a) n adding excess f ammnium hydrxide t a cpper chlride slutin a deep blue slutin f [ Cu( N 18 (d) ( N ) S KCN N ) ] in is frmed CN KS N C N Urea 185 (a) Nitric acid turns the skin yellw because it reacts with prtein giving a yellw cmpund called xanthprtein 186 (d) Ammnium sulphate is a nitrgenus fertilizers 187 (d) Ammnia generally prepared by the aber s prcess 19 (a) is hypphsphrus acid 19 (c) ( N ) S is a salt f weak base & strng acid ( N S ) S N Weak base Strng acid 19 (a) ne part f cncentrated N and parts cncentrated Cl frm aquaregia 196 (c) t +5 ( ) and 5) : : : ( 199 (b) BiCl 5 des nt exist because + xidatin state f Bi s mre stable than +5 due t inert pair effect 00 (c) Tribasic acid grups are present : : : :: :: :: : : : : : 01 (d) 0 (c) Na Na It can give in in slutin N and bth are basic because f the presence f lne pair f electrns N As Sb Bi 0 (b) Stability decreases dwn the grup because bnd energy decreases dwn the grup 0 (a) Nitrgen frms N which is mst basic 05 (b) is a diabasic acid It frms tw types f salts Na and Na 06 (a) N C N N C N 07 (c) I II III IV V Element N As Sb Bi Atmic n (c) grup are present it is inizes in three steps because three 1 (c) Ca Ca( ) 1 (d) ( N ) Cr 7 N Cr 1 (b) B As Bi As we g dwn the grup bnd angle decreases because repulsin between bnded pairs f electrn decreases 15 (b,c) N Cl N N N Cl 17 (a) Acidic character f xides decreases dwn the grup 18 (d) N 7 1s, s, p d-rbitals absent in secnd sub-shell 0 (c) N can frm NCl, N5 and Ca N but des nt frm NCl 5 1 (a) ighest xidatin state is +5 which remains unchanged (a) ypphsphrus acid ( ) is a mnbasic acid which act as reducing agent In this mlecule tw bnds are respnsible fr its reducing character and ne bnd is respnsible fr its mnbasic acid character (a) Bne black is the plymrphic frm f phsphrus (b) Nitrus xide is knwn as Laughing gas 5 (a) We knw that, b( N N ) b S nitric xide ( N) is prduced 6 (d) hsphrus exist as slid at 7 C and 1 atmspheric pressure (mp f white phsphrus = C) 7 (b) We knw that, N 10 N5 The prduct is dinitrgen pentaxide ( N 5)

11 s and p-blck Elements (b) ypphsphrus acid is 9 (b) 0C ( g) N( ) (Blue) N( g) N l 0 (c) The ignitin temperature f black phsphrus is highest amng all allttrpes 1 (a) ( N ) Cr7 N Cr N N N (a) Nitrgen shws I t V, all xidatin states (c) Biling pints f Sb 5 K), N (8 ), ( K (185 K As (11 ) and ) therefre biling pints K are f the rder Sb N As (a) Because phsphrus is mst electrnegative element ut f, Bi, Sb and C 5 (d) Ca( ) Si CaSi 5 6 (a) When a slid cmpund n heating change int gaseus state withut changing int liquid state, the phenmenn is knwn as sublimatin eg, I, N Cl and camphr 7 (b) 16 bnd by its structure 8 (d) hsphrus is a nn-metallic element It frm s acidic xide 5 9 (b) N N N Mixed acidanhydride 0 (c) xidatin number f As in As x 8 1 x 6 1 x 5 1 (a) The inrganic nitrgen exists in the frm f ammnia, which may be lst as gas t the atmsphere, may be acted upn by nitrifying bacteria, r may be taken up directly by plants (c) Sulphur xygen family (1) Mnclinic () Rhmbic () lastic (c) S S 5 (a) 1 S 8 e 8 S 6 (c) 9 (b) 8 1s s p 11 (a) Element S Sc Te Electrnegativity (b,c) Na S S Na S S ( S ) ( aq) unpaired electrns ( aq) ( l) ( g) 15 (d) S Se Te As we g dwn the grup electrnegativity decreases due t which repulsin between bnded pairs f electrn als decreases ence, bnd angle decreases 0 (a) aramagnetism because f tw unpaired electrns in the antibnding mlecular rbitals 1 (a) NaS NaS (c) 8 (b) [ ] KI K I [ ] KI K I (d) KMn S 5 S K S MnS 8 5S (a) Cu S CuS S 5 (a) The minimum and maximum xidatin number f S are and +6 respectively Since the xidatin number f S in S is +, therefre it can be either increased r decreased Therefre S behaves bth as an xidising as well as reducing agent 6 (a) S S S reducing agent xidising agent 7 (d) K Cr 7 S S 9 (a) S Mg Mg S K S Cr ( S ) Green 0 (a) S S [ ] (nascent hydrgen) Clured flwer [ ] Clurless flwer 1 (c) S Na Na S Sdium (a) S S (d) sulphite S S S 7 (leum) 5 (b) Ag S AgS S Reducing agent xidising agent 6 (a) nly dehydrating agent 8 (b) 51 (d) 5 (d) S C C C cnc S C C C S S 7 S S S 55 (d) Na S S Na S S 7 (leum r uming S ) 56 (b) Na S Cl Na S Cl S silent electric discharge 58 (c) AgBr Na S Na [ Ag( S ) ] NaBr 60 (a) S S S 6 (a) S S 6 (a) Mixture f K Cr7 and cnc S is knwn as chrmic acid

12 80 s and p-blck Elements 65 (c) cntain hydrgen bnd while n hydrgen bnding is present in S 67 (a) cntaining hydrgen bnd 69 (c) S Cl5 Cl S Cl S Cl5 70 (d) Mixture f and C Cl Cl S Cl Cl Cl Sulphuryl chlride 71 (c) The bnd between ( Te) is weakest hence it gives easily 7 (c) K because in (superxide in) in ne unpaired electrn is present in the antibnding rbital 75 (b) xidatin states are,, 6 77 (b) S Se Te 7K 1K 69K K S has lwest biling pint and has highest biling pint because if any cmpund has hydrgen bnd Its biling pint is high 78 (c) V 5 catalyst are used fr the manufacture f S by Cntact prcess 81 (d), S, Se shws plymrphism 8 (e) S N N S 85 (b) is similar t that f 87 (d) 16th grup called chalcgens (xygen family) while Na is a Ist grup element which is called alkali metal 90 (b) Car s acid ( S5) 91 (c) K C K C 9 (a) cnsist f highest biling pint than ther hydride (Due t presence f the hydrgen bnding) 9 (b) Lse f electrn 95 (c) S is sluble in water 18Å S Sulphurus S acid 96 (c) Na Na In this reactin xygen ( ) is frmed biling S 97 (b) Na Na S Na S 98 (c) Quartz is a crystalline variety f silica 99 (b) 98% S is used fr absrbing dense fg f acid which is frmed by disslving S in water ence 98% S is the mst efficient agent fr the absrptin f S 100 (b) Cncentrated S is diluted by adding the cnc S in the water drp by drp with cnstant stirring because it is an exthermic reactin and by ding s heat is generated slwly and dissipated in the atmsphere 101 (a) htchemical smg is caused by xides f sulphur and nitrgen 10 (d) S act as bleaching agent due t its reducing prperty S S Clured matter + Clurless matter 10 (b) zne n treatment with S prduce S S S 10 (b) b is a pwerful xidizing agent and liberate when treated with acids S, gas will be evlved 105 (c) Dithinus acid S ) has sulphur in + xidatin state ( S S ; ( 1) x ( ) 0 x 8 6 ; x 106 (a) S acts as an xidising agent particularly when treated with strnger reducing agents S xidises 107 (a) R SiCl n hydrlysis frms nly a dimer R Si SiR RSi SiR S int S 108 (d) rmatin f chlrine nitrate is the main cause f zne deplictin algen family 1 (b) > Cl > Br > I (Thermal stability) (a) CCl 1 CCl Cl hsgene r carbnyl chlride (d) Idine has the least affinity fr water and is nly slightly sluble in it wever, it disslves in 10% aq slutin f KI due t the frmatin f a cmplex in ie I I KI KI r I I (c) NaS I NaI NaS 6 I (cmplex in) 5 (a) Cl KBr KCl Br A mre electrnegative halgen can displaces less electrnegative halgen 6 (a) I is the strngest reducing agent amng halgen acids because f lwest bnd dissciatin energy 8 (a) Due t -Bnding free ins are nt present in aq slutin ence, bad cnductr 9 (c) Electrnegativity f I is less than Br Therefre unable t displace brmine 10 (b) Carnellite is KCl MgCl 6 The mther liqur life after crystallisatin f KCl frm carnellite cntain abut 05% f brmine as and KBr MgBr 11 (a) is liquid because f intermlecular -Bnding 1 (a) 1 (d) Cl Weak acid (dil) Cl Strng ba cnjugate se Cld Na Cl NaCl NaCl Sd hypchlrite

13 s and p-blck Elements 81 (cnc) heat 6Na Cl 5NaCl NaCl Sdium chlrate 15 (b) 6K Cl 5KCl KCl 17 (a) is the weakest acid Since it is unable t give which are trapped in -Bnding 18 (b) ydride Cl Br I Bpt (in K) Becuse f having lw bp Cl is mre vlatile 19 (a) KCl I KI Cl 0 (c) NaS I NaI NaS 6 ins 1 (d) KMn 16Cl KCl MnCl 5Cl 8 (a) Cl Cl Cl Cl As the xidatin n f halgen increases acidic character increases 5 (c) KBr S Mn KS Br MnS 9 (b,d) Electrn affinity f is maximum Cl Element Cl Br I EA kj/mle Biling pt (C) (a) Cl NaBr NaCl Br (d) CCl N reactin d-rbitals are absent in carbn atm (a) 10N I 10N I 5 (d) KI I KI 6 (a) KBr S K S Br 7 (b) (b) CuS KI CuI KS CuI I CuI Cuprus idide (d) As the atmic number increases electrnegativity decreases ence, tendency t gain electrn decreases 51 (a) Cl Cl Br Br I I 5 (d) Br KI I KBr 56 (d) 58 (c) 6 NaCl Na Cl Reductin (ande) 59 (a) Mn Cl MnCl Cl Electrlysis (cathde) 61 (b) NaCl Na Cl 6 (c) Cl Cl Cl Expsed t air (aq) ( g) Cl Cl [] r Cl Cl ( g) 6 (a) Na Cl NaCl NaCl 66 (b) Cl Cl [ ] Nascent xygen Bleaching Clured [ ] Clurlessflwer flwer agent (xidized) 68 (b) Ca Cl CaCl NaC Cl N reactin 69 (c) Ca( ) Cl CaCl Slaked lime 71 (b) MgBr Cl MgCl Br 7 (a) Cl Br Cl Br 7 (a) KI S KS I Cnc Cnc S 7 (b) NaI Cl KCl I CCl I Vilet clur I I S Vi let vapur 76 (b) KI S KS I S I I S 79 (c) KI S KS I 80 (b) Vilet vapur I is frmed but it is further xidised by cnc S int I I S I S Cl Cl (aq) ( aq) Vilet vapur 81 (b) NaCl K Cr S 7 K S NaS CrCl Chrmyl chlride 8 (c) ydrgen bnding is absent in I while it is present in N, and C 5 8 (d) In case f I due t large size f idine strng Vander Waal frces are present ence, it has highest mlar heat f vaprisatin 85 (d) I is strngest acid because I bnd is weakest amng halgen acids 86 (a) In the mlecules aggregate because f intermlecular hydrgen bnding ence, it has highest biling pint 88 (a) sp -hybridizatin and tw lne pairs n halgen Cl has which prduces V-shape Bent structure Cl 89 (d) Cl Cl 7 90 (b) Cl Br I gases liquid slid

14 8 s and p-blck Elements As we g dwn the grup Vander Waal frces increases ence, physical state changes 9 (c) can nt act as reducing agent because it has highest reductin ptential e ; E 87 V 9 (c) 10N I 10N I 9 (a) I5 I7 95 (a) seudhalide ins and seudhalgens There are certain mnvalent negative ins made up f tw r mre electrnegative atms which exhibit prperties similar t these f halide ins Such ins are knwn as pseud halide ins just as halide ins, pseud halide ins have als crrespnding dimric mlecules These are called pseud halgens and shw prperties similar t thse f halgens seudhalide seudhalgens CN cyanide (CN ) Cyangen SCN Thicyanate (SCN ) Thicyangen 96 (c) Na is highest melting halide because it is mst inic in nature 98 (b) 99 (c) CaCl CaCl [ ] Nascent xygen 100 (a) Generally alkali metals and alkali earth metals elements extracted by the fused electrlysis methd 10 (c) Na S I NaI Na S 6 10 (b) Beilstein test In this test rganic cmpund is heated n a cpper wire in a flame The appearance f a green r bluish green flame due t the frmatin f vlatile cupric halides indicate the presence f halgens in the rganic cmpund (It des nt tell which halgen is actually present) 105 (d) 0 Cl KBr Reductin Br 1 K Cl 107 (b) Cl N NCl Cl xidatin 108 (a) UV Cl Cl Cl Cl ree radical 109 (a) is a weak acid due t intermlecular hydrgen bnding 110 (a) Acidic nature f xide Nn metallic nature f element Nn metallic nature decrease in the rder Cl S 111 (c) Aqua regia is 1 part f N and part f Cl 11 (a) AgI is a cvalent cmpund 11 (a) Brmine is a liquid at rm temperature 115 (a) Cl Cl [ ] Nascent xygen 117 (b) The enamel f ur teeth is the hardest substance in the bdy made up f Ca and dentine belw it made f Ca ( ) 118 (b) As the electrnegativity decreases reactivity als decreases 119 (b) KI I KI 11 (d) I I (sluble cmplex) ICl I (a) Cl Br Cl As we g dwn the grup bnd energy decreases hence, acidic nature increases 1 (b) Caliche is crude chile salt petre ( NaN ) which cntains abut 00% idine as sdium idate ( NaI ) 1 (a) Li LiCl LiBr LiI Lattice energy depends n the size and charge f the in 15 (a) - mre strng bnd cmpare t -Cl, -Br and Cl-Br bnd 16 (c) Na S I Na S NaI 17 (d) 6 CaCl( Cl) Ca Cl Cl 18 (a) Na Cl NaCl NaCl Na Cl Na Cl 11 (d) Na I I NaBr N reactin I NaCl Because I is least electrnegative amng halgens 1 (a) Cl Cl S N Decreasing rder f acidic character 1 (a) gcl g( CN ) gcl g( CN ) Mercuric chlride Mercuric cyanide 15 (a) I Br Cl Acidic character decreasing rder 16 (c) Ca( Cl CaCl Cl ) Slaked lime Bleaching peder 17 (d) KCr 7 1Cl KCl CrCl 7 Cl 19 (d) lurine des nt gives psitive xidatin state it is always shw 1 xidatin state 10 (a) 7 5 Cl Cl Cl 1 Cl 11 (d) Ca ( ) Cl CaCl bleaching pwder 16 (a) ( dil) Na Na 17 (a) lurine can nt be xidised by even strngest xidising agent 18 (b) Br S S Br 19 (c) KBr I KI Br Idine is a less electrnegative cmpare t Brmine hence idine des nt change Br t Br 150 (a) CaI are shw cvalent prperties than ther Ca, CaCl, CaBr cmpund 151 (d) KMn S 10Cl K S MnS 8 5 Cl 15 (d) bi is least stable because f tw reasns (1) Size f idine is biggest () xidatin state f b is mre stable than state because f inert pair effect 15 (a) Cl Na N reactin Since Cl is less electrnegative then Therefre unable t displace flurine frm its salt I 156 (b) CS Cl CCl S Cl 157 (b) Accrding t the ajan s rule largest catin and smallest anin 158 (a) Na 159 (c) Cl Cl ve 1 mle mles

15 s and p-blck Elements 8 igh temperature and lw pressure is favurable 160 (d) B accept lne pair f electrns 161 (d) Cr Cl is a range red gas 16 (a) lrine always shw -1 xidatin state 165 (a) Slid Na is used t purify flurine ie by remving f fumes 166 (c) K K K K At cathde : K e K K K At ande : e 168 (c) Small atmic size f Li and lattice energy is highest 169 (b) S bleaches flwer by reductin S S [ ] Reductin [ ] Clured Clurless flwer reduced flwer This bleaching is temprary because reduced flwer again xidised by air t frm clured flwer Cl Cl [ ] xidatin [ ] Clured Clurless flwer xidised flwer This bleaching is permanent because xidised flwer remains clurless 170 (a) lurine des nt frm xyacids because it is mre electrnegative than xygen 17 (c) Mn Cl MnCl Cl KMn S 10Cl 175 (b) KCl S K S MnS 8 5 eat Cl KS Cl Cl 176 (b) Cl Br I As the size increases electrnegativity decreases 177 (c) Inic radius increases n ging dwn the grup because n f shells increases 178 (b) Reducing prperties increase frm t I s it xidise by nitric acid I 10N I 10N 179 (a) lurine and chlrine are mre electrnegative than sulphur 180 (d) Upper halgen can replace lwer halgen frm their cmpunds slutin 181 (a) Idine ( I ) is slightly sluble in water but it disslves in 10% aqueus slutin f KI due t the frmatin f ptassium tridide KI ) ( 18 (a) Due t highest electrnegativity f flurine the anin [ ] exists as a result f strng hydrgen bnd by which K assciate t frm K 18 (a) lurine is the mst electrnegative element It des nt frm xyfluxides like ther halgens If reacts with Na t frm sdium fluride and xygen fluride Na Na 18 (c) Due t unpaired e Cl is paramagnetic 185 (a) xidatin number f Br is mre than that f Cl, N and s it is the strngest acid amng these 186 (a) Chlrine heptachlride ( Cl 7 ) is the anhydride f perchlric acid Cl Cl7 187 (c) I frms cmplex in disslves in it I in KI slutin due t which it Nble gases (a) Gas e N Ml mass 8 5 (c) elium (In Greek elis = Sun) 6 (d) All the nble gases are mnatmic, clurless and durless gases Their mnatmic nature is due t the stable uter cnfiguratin ns np 6 f their atms As a result, they d nt enter int chemical cmbinatin even amngst themselves 7 (c) Except e, all ther nble gases are adsrbed by ccnut charcal at lw temperatures The extent f adsrptin increases as the atmic size f the nble gas increases 10 (b) An xygen-helium mixture is used artificial respiratin in deep sea diving instead f air because nitrgen present in air disslves in bld under high pressure when sea diver ges int deep sea When he cmes t the surface, nitrgen bubbles ut f the bld due t decrease in pressure, causing pains This disease is called bends 11 (c) Xe, Xe Xe, Xe Xe 6, Xe 1 (c) Gas (Abundance in air by vlume (ppm)) elium 5 Nen 18 Argn 9 Kryptn 11 Xenn (c) Nen Ne is mnatmic and thers are diatmic N, and 1 (c) 1 1 e 15 (b) e des nt exist 16 (d) Ar 18, 8, 8 17 (b) Ne 10 (d) Xe has : Xe 1s s p sp d 6 hybridizatin with linear shape (b) artial hydrlysis; Xe Xe Cmplete hydrlysis; Xe Xe Xe 6 6 (d) e is least plarizable because f small atmic size 7 (a) Rn because it is radiactive element btained by the disintegratin f radium

16 8 s and p-blck Elements Ra 86 Rn e 0 (c) 1s s p Nen 5 (a) Xe Xe (c) Xe Kr Ar Ne e Slubility in decreasing rder 7 (d) d sp hybridizatin sp hybridizatin sp d hybridizatin 8 (b) Zer grup element are shw less chemically activity because this grup element have 8 electrn 9 (d) Xe is frmed fllwing cmpunds Xe, Xe, Xe 6 0 (a) As the number f shells increases, size increases and the effective nuclear charge n the utermst electrn decreases Thus, IE decreases (c) Xe, Xe & Xe6 can be directly prepared Xe Ni tube 67 K Xe ; Xe Xe 67 K 6 atm 5 57 K Xe Xe atm Xe is btained by the hydrlysis f Xe 6 Xe Xe 6 6 (a) Xe shws 6 sp hybridizatin 7 (a) It is because (1) Small atmic size () igh Inizatin energy () Absence f d-rbitals 8 (a) Zer grup element are attached with weak intermlecular frce 9 (b) Xe, Xe, Xe 6 50 (d) Xe : Xe : Xe6 : Xe Xe Xe Xe Xe 6 51 (d) Neil Bartlett prepared first nble gas cmpund Xenn hexaflurplatinate (IV) 5 (d) e, Ne, and Kr all are fund in very little amunt in atmsphere, s all are called rare gas 5 (c) elium is twice as heavy as hydrgen, its lifting pwer is 9% f that f hydrgen elium has the lwest melting and biling pint f any element which makes liquid helium an ideal clant fr many extremely lw temperature applicatin such as super cnducting magnet and crygenic research where temperature clse t abslute zer are needed 55 (a) The maximum temperature at which gas can be liquified is called its critical temperature The gas which have high biling pint will change int liquid first and s critical temperature f the gas will be mre T C B and B Mlecular weight S Kr liquifies first 56 (c) Suppse the xidatin state f Xe is x Xe x ( ) ( 1) 0 x 0 x 57 (a) e Ne Ar Kr Xe Rn Biling pint f Inert gases 59 (d) Xe is highly plar since the inisatin ptential f xenn is quite clse t the inisatin ptential f xygen 60 (d) In the frmatin f Xe, sp d hybridisatin ccurs which gives the mlecule an ctahedral structure The xenn and fur flurine atms are cplanar while the tw equatrial psitins are ccupied by the tw lne pairs f Xe electrns Critical Thinking Questins 1 (c) Crrect sequence is N CN N N N N N Cl (d) Secnd grup elements are shw strng reducing prperties but less Ist grup element shw less (a) The size f alkaline earth metals is smaller as cmpared t its crrespnding alkali metals and its effective nuclear charge is als mre than that f its crrespnding alkali metals (d) Lead is maximum in flint glass eat 5 (b) BaS C BaS C Thus, n heating they prduce BaS C 6 (d) Smaller the atmic size tendency f hydratin is mre as the size increases tendency fr hydratin als decreases 7 (a) usin mixture is NaC KC 8 (b) Cl is a gas 9 (a) (A) erxide is () ; (B) Super xide is K () 10 (a) (C) Dixide is b () ; (D) Subxide is C (1) S S 98% S 7 leum (uming S ) 11 (c) Sn Na Na Sn 1 (b) Sn Cl SnCl Na Al Na e NaAl Sd metaaluminate (Sluble in Na ) N reactin (Insluble in Na)

17 s and p-blck Elements 85 1 (d) The cmpsitin f the cmmn glass is Na Ca 6Si 1 (c) Lead frm nitric xide with dil N 15 (b) b 8N b( N) N 16 (d) rder f acidic strength is Te Se S Na is a salt f Na and is least acidic amng given acids hence p in this case will be maximum 17 (a) N is the strng xidising acid s it react with alkali while rest can be react with bth and alkali 18 (d) Zer grup is called a buffer grup because it lies between highly electrnegative halgens and highly electrpsitive alkali metal element 19 (c) bs is insluble in water 0 (a) N 5 is mst acidic 1 (b) Element lurine Chlrine Brmine Idine BE in kj mle under (d) CaCN CaC N znlysis pressure (a) 6 Cmplete znalysis gives vlume f zne (b) Marble statue CaC ; Calcinated Gypsum CaS ; Sea shell CaC ; Dalmite CaC MgC 5 (b) Sdium is basic in nature 6 (c) I I I Xe 7 (a) The hydratin energy decreases frm Be t Ba This causes the decrease in the slubilities f the sulphates in this rder In ther wrds, the slubilities decreases with increase in the inic size 8 (d) Mg Mg Mg N Mg N 9 (a) Zn Ba BaZn 1100 C 0 (b) There are n free electrn in N, s it is dimagnetic in nature 10 C (b) CaS CaS 1 Gypsum lster f paris 0 (d) Third alkaline earth metal is calcium 0 Ca N f electrn are 0 & N f prtn are 0; e/0, p/0 (a) In the cmpunds f alkaline earth metals all the electrns are paired ence, they are diamagnetic in nature (a) Mixture f helium and xygen is used in artificial respiratin 5 (a) Alkaline slutin f pyrgalll quickly absrbs xygen 6 (d) N N N NaN N Na Therefre, ttal number f lne pair f electrn n central atm Xenn =1 ( N ) Cr7 N Cr 7 (b) Because yellw phsphrus is mst reactive frm f phsphrus and is highly plymerised 8 (c) Carbn has electrns in their penultimate shell cnfiguratin s due t d-rbital in penultimate shell is false statement 9 (d) All ther xides f nitrgen except N and N are acidic in nature 0 (a) bcl bcl CaCl NaCl is the increasing rder f inic character 1 (a) Si Cl SiCl silicnchlrfrm (a) K is used in xygen cylinder because it absrbs C and increases cntent Super xides reacts with water t give & (d) NaC and Na C decmpses t give C which extinguish fire (d) Ca is insluble in water 5 (a) Cl is mst acidic 6 (b) CsCl KCl NaCl LiCl 7 (d) Na S I Na S NaI 8 8 (b) In general, higher the xidatin state, mre is the cvalent character f the xide I 7 & I 5 d nt exist I is inic in nature It is infact idyl idate cvalent xide is I 5 9 (b) LiAl act as reducing agent LiAl C C C C [ I ] [ I ] The nly 50 (c) When cnc Cl react with ptassium chlrate t gives Cl Cl 51 (c) S S S 5 (b) Lithium nitrate n heating gives LiN Li N ( S) ( S ) 5 (d) CaC NaC KC is the Increasing rder f slubility 5 (c) Nitrlim is CaCN C 55 (a) The xidatin state f halgens is same +1 Therefre the acidic character depends nly upn the electrnegativity igher the electrnegativity f the halgen mre easily if will pull the electrns f bnd tward itself and hence, strnger is the acid 56 (c) Iridium [ I, Z 77] is nt belng t nble gas 57 (c) Name and basicity f is hypphsphrus acid & ne 58 (c) In N there are free electrn s it is paramagnetic in nature 59 (a) Nessler's reagent is K gi 60 (b) elium was firstly discvered by willium Ramsay 61 (c) 166 Since inert gases are mnatmic 6 (c) In this reactin, phsphrus is simultaneusly xidised t Na and reduced t ence this reactin is an example f disprprtinatin

18 86 s and p-blck Elements Na 1 Na 6 (c) Reductin is accmpanied by an increase in xidatin number f the reducing agent C belng t IVA s the max-n is + In C the xidatin number f C is +, which cannt be further increased ence, C can nt act as reducing agent 6 (b) When silicn tetra fluride reacts with water Si6 and Si 6 are frmed Si Silicntetrafluride Water Si Si 65 (a) 6I( dry) I 66 (c) Na( N ) (Micrcsmic salt) 67 (b) Thermite mixture e Al 6 Whitesilicic acid 68 (d) The clur f liquid is pale blue 69 (a) elium is nt sluble in bld even under high pressure, a mixture f 80% helium and 0% xygen is used instead f rdinary air by sea divers fr respiratin 70 (a) Mg N 6 Mg( ) N 71 (a) Calcium cyanamide n treatment with steam prduce CaC N Assertin & Reasn 1 (b) Sulphate is estimated as BaS because f high lattice energy in a grup (b) lurine is a strng xidising agent than ther halgens due t highest electrnegativety (a) In N due t presence f tw N- bnds it is a strnger acid than N 6 (c) Bleaching actin f chlrine carried by xidatin while bleaching actin f S carried by reductin 7 (b) n heating its utermst electrn transite t next energy level by which it becme mre reactive 10 (a) K and Cs emit electrns n expsure f light due t lw inisatin ptential 11 (e) The lwer value f bnd dissciatin energy f - bnd due t lnger inter electrnic (electrn - electrn) repulsin between the nn-bnding electrns in the p rbitals f flurine atm 1 (a) It is fact that halgens are highly reactive as they have seven electrns in their utermst rbit and they want t stabilize by acquiring an electrn Therefr, they d nt ccur in free state ere bth assertin and reasn are true and the reasn is the crrect explanatin f assertin 1 (a) Lithium frms lithium xide This is due t the fact that Li in has smallest size and it has a strng psitive field arund it Therefre, it stabilize in with strng negative field arund it Thus, bth assertin as well as reasn are true 1 (a) Liquid N is used fr refrigeratin is true and it is due t the fact that is vaprises quickly and fr vaprisatin it takes up heat and cl the refrigeratr ence assertin and reasn bth are true 15 (a) It is true that Al () The reasn is that Na is a strng alkali, it disslves Al () Which is amphteric in nature and frms NaAl Al( ) Na NaAl Sdium meta aluminate 16 (c) Brn is metallid Thus assertin is crrect Metallids pssess, metallic as well as nn-metallic nature ence, reasn is false 17 (b) It is crrect that inert gases are mnatmic because fr inert gases C / 1 66 p C v 18 (c) When Mg is burnt in nitric xide it cntinue t burn because during burning the heat evlved decmpse N t N and xygen thus, prduced helps Mg t burn ere assertin is true but reasn is false 19 (d) Anhydrus Ba is nt used fr preparing because it reacts with S and the reactin ceases after sme time due t frmatin f BaS n Ba Therefre, assertin and reasn bth are false 0 (d) Inrganic benzene, brazine is highly reactive while benzene is much less reactive ere, assertin is false, but reasn is true 1 (a) The halgens absrb visible light due t which all halgens are clured ence, bth assertin and reasn are true and reasn is crrect explanatin (b) It is true that barium is nt required fr nrmal bilgical functin in human beings and it is als true that it des nt shw variable xidatin state It nly shws + xidatin state (d) The bnd length is shrter in than in due t higher electrnegativity is a nn inic cmpund ere bth assertin and reasn are false (d) ere bth assertin and reasn are false because bi is nt a stable cmpund and idine can nt stabilize higher xidatin states b shws (II) xidatin state mre frequently than b (IV) due t inert pair effect 5 (b) Bth assertin and reasn are true but reasn is nt crrect explanatin f the assertin Enamel the hardest substance f the bdy is cmpsed f flurine nt magnesium Magnesium is an essential element as it acts as a factr f many enzymes f glyclysis and a number f ther metablic reactins dependent upn AT 6 (d) Bth assertin and reasn are false Radium is the rarest f all s-blck elements cmprising nly percent f igneus rcks rancium (s-blck member) is radiactive; its lng lived istpe 1 minutes 7 (c) Assertin is true but reasn is false Due t high plarizing pwer f cmpund 8 (c) Assertin is true but reasn is false r has a half life f nly Li, LiCl is a cvalent Be has fully filled s rbital which gives a relatively mre stable electrnic cnfiguratin 9 (a) Bth assertin and reasn are true and reasn is the crrect explanatin f assertin 0 (a) Bth assertin and reasn are true and reasn is the crrect explanatin f assertin