Q. No. 6 alomel is the name of : Hgl Hg l Hgl + Hg Hg l + Hg Explanation Factual Q. No. 7 ZnO shows yellow colour on Heating due to : d d transition T

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1 Q. No. 1 hemically philosopher of wool is : ZnO ao Hgl Hg l Explanation Philosopher s wool ZnO (Factual) Q. No. oiling ul with u in conc. Hl gives : ul ul H[ul ] u l Explanation ul + u ul Q. No. 3 Thermal decomposition of zinc nitrate give : Zn ZnO Zn(NO 3 ) NO Explanation Zn NO ZnO + 4NO + O 3 Q. No. 4 Malachite and azurite are used respectively are : lue and green pigment Red and green pigment Green and blue pigment Green and red pigment Explanation Malachite green factual zurite lue Q. No. 5 Mercury is transported in the containers made of : g Pb l Fe orrect nswer 4 Explanation Factual

2 Q. No. 6 alomel is the name of : Hgl Hg l Hgl + Hg Hg l + Hg Explanation Factual Q. No. 7 ZnO shows yellow colour on Heating due to : d d transition T spectra Higher polarisation caused by Zn + ion F centres orrect nswer 4 Explanation Factual Q. No. 8 When steam is passed over red hot iron, the substances formed are : Fe O 3 + H Fe 3 O 4 + H FeO + H FeO + H + O Explanation 3Fe 4H O Fe O 4H 3 4 Steam Q. No. 9 Verdigris is : asic copper acetate asic lead acetate asic lead None Explanation u H OO.u OH Verdigris 3 asic copper acetate Q. No. 10 Which of the following is the correct formula for a compound of scandium and oxygen? S O SO S 3 O S O 3 orrect nswer 4 Explanation S O 3 S +3 is the only stable cation of sc

3 Q. No. 11 Mercury on heating with aqua regia gives : Hg(NO 3 ) Hgl Hg(NO ) Hg l Explanation + Hg + Hl Hgl + H Q. No. 1 hloroplatinic acid is : monobasic dibasic tribasic tetrabasic Explanation H [Ptl 6 ] Q. No. 13 Fe is made passive by : dil. H SO 4 dil. Hl conc. HNO 3 conc. H SO 4 Explanation conc HNO 3 renders Fe passive Q. No. 14 Na O 3 + Fe O 3 +O what is in the reaction? NaFeO Na 3 FeO 3 Fe 3 O 4 Na FeO Explanation Na O +Fe O NaFeO + O 3 3 sodiumferrate Q. No. 15 Ferrous sulphate on heating gives : SO and SO 3 SO only SO 3 only H S only Explanation FeSO Fe O + SO + SO 4 3 3

4 Q. No. 16 Iron is protected by coating it with a thin layer of : u Zn Pb Mg Explanation nodizing Q. No. 17 The formula of azurite is : uo 3. u(oh) uo 3. u(oh) uo 3.u(OH) uso 4.u(OH) Explanation zurite uo 3. u(oh) Q. No. 18 Oxide of metal cation which is not amphoteric? l 3+ r 3+ Fe 3+ Zn + Explanation NaOH l O NalO 3 3 ll3 NaOH 3 rl3 3 rl3 + NaOH NaZnO + Znl l O r O r O Zn Zn Q. No. 19 Philosopher s wool when heated with ao at gives the compound : ado a + ZnO ao + Zn azno Explanation ao + ZnO azno (key correction) Q. No. 0 Gold dissolves in a aqua regia forming : uric chloride urous chloride hloroauric acid urous nitrate Explanation u+ 3HNO 3 + 4Hl H ul 4 + 3NO + 3H O H ul4 OR u+hno 3 + 4HlHH ul 4 +NO+H O

5 Q. No. 1 The solubility of silver bromide in hypo solution is due to the formation of : g SO 3 g S O 3 [g(s O 3 )] [g(s O 3 ) ] 3 Explanation (key correction) gr + Na S O 3 Na 3 [g(s O 3 ) ] + Nar Q. No. Sodium thiosulphate is used to remove the unexposed gr from photographic films by forming a complex. In this complex of silver, the coordination number of silver is : Explanation Na3 g S O 3 bidendate ligards,sos.v = 4 Q. No. 3 The false statement about iron (III) hydroxide is that : it is a weaker base than Fe(OH) with concentrated KOH, it forms a complex K 3 [Fe(OH) 6 ] it gradually loses water and transforms into Fe O 3 it exhibits amphoteri properties with acid ones predominating orrect nswer 4 Explanation Its not amphoteric, its acidic Q. No. 4 gno (W) + (X)+ O 3 (X)+H O HNO +HNO (W)+HNO 3 Y +NO+H O 3 (Y) +Na S O (excess) (Z)+NaNO Identify (W) to (Z). 3 3 W = g X = N O Y = gno 3 Z = Na [g(s O 3 ) ] W = g O X = NO Y = gno 3 Z = Na 3 [g(s O 3 ) ] W = g X = NO Y = gno 3 Z = Na 3 [g(s O 3 ) ] W = g O X = N Y = gno 3 Z = Na[g(S O 3 ) ] Explanation gno g+ NO + O 3 w X NO +H O HNO +HNO X 3 3 g + 4HNO 3gNO +NO +H O W 3 3 Y

6 gno + Na S O Na g S O +NaNO Y Z Q. No. 5 The oxidation state of copper changes when aqueous copper (II) ions react with : (I) NaOH (aq) (II) Fe(s) (III) KI (aq) I, II, III II only II, III I only Explanation uso + NaOH u OH +Na SO uso + 4KI u I +K SO +I uso +Fe FeSO +u O Q. No. 6 blood red colour is obtained when ferric chloride solution reacts with : KN KSN K 4 [Fe(N) 6 ] K 3 [Fe(N) 6 ] Explanation +3 3KSN Fe Fe SN 3 blood red Q. No. 7 The compound in which nickel has the lowest oxidation state is : Ni(O) 4 (H 3 OO) Ni NiO Nil (PPh 3 ) Explanation Ni O 4 O Q. No. 8 Spiegeleisen is an alloy of : u + Zn + Ni Ni + r Mn + Fe + Fe + r + Ni Explanation Fe + Mn +

7 Q. No. 9 Hgl is a covalent compound, sparingly soluble in water, the solubility increases by the addition of chloride ions due to : common ion effect formation of complex [Hgl 4 ] weakening of Hg l bonds strong ion dipole forces Explanation Hgl + l Hgl 4 Soluble Q. No. 30 Silver nitrate solution is kept in brown bottles in laboratory because : it reacts with ordinary white bottles brown bottles cut the passage of light through brown bottles do not react with it ordinary bottles catalyse its decomposition Explanation gno 3 gets decomposed by light Q. No. 31 opper is very slowly oxidised on the surface in moist air, giving a green coating of verdigris. Verdigris is : u O uo 3 u(h 3 OO). u(oh) uso 4 Explanation Factual Q. No. 3 Fe(OH) is precipitated from Fe(II) solutions as a while solid but turns dark green and then brown due to the formation of : Fe(OH) and Fe(OH) 3 only Fe(OH) 3 Fe O 3. (H O) n Fe O 3. H O Explanation Factual Q. No. 33 Give the correct order of initials T or F for following statements. Use T if statement is true and F if it is false. (I) Sulphide ions reacts with Na [Fe(N) 5 (NO)] to form a purple coloured compound Na 4 [Fe(N) 5 (NOS)]. In the reaction, the oxidation state of iron changes. (II) Pt(IV) compounds are relatively more stable than NI(IV) compounds (III) The welding of magnesium can be done in the atmosphere is Helium (IV) LilH 4 on hydrolysis will give H FFTT FTTT TFTF TFTT

8 Explanation Na Fe N NO 5 + doesnt change Na4 Fe N NOS 5 + F (III) is true (Factual) (T) 4H O 4 3 (IV) LilH 4H +LiOH+ l OH T Q. No. 34 Sodium thiosulphate, Na S O 3. 5H O is used in photography to : Reduce the silver bromide to metallic silver onvert the metallic silver to silver salt remove undercomposed gr as soluble silver thiosulphate complex remove reduced silver Explanation Na S O + gr Na g S O +Nar Q. No. 36 Mark the correct statements : Hg forms an amalgam with iron Hg vapour is non poisonous Hg is monovalent in mercurous compound Oxysalts of mercury are thermally unstable orrect nswer 4 Explanation They are quite stable Q. No. 37 Mercury is the only metal which is liquid at 0º. This is due to its : Very high ionisation energy and weak metallic bond Low ionisation potential High atomic weight High vapour pressure Explanation onceptual Q. No. 38 white precipitate of gl dissolves in excess of : (I) NH 3 (aq) (II) Na S O 3 (III) NaN III only I, II, III I, II I only Explanation NH + gl 3 g NH 3 g S O g N 3 3

9 Q. No. 39 Which of the following statements regarding copper salts is not true? opper (I) disproportionates to copper and copper (II) ion in aqueous solution opper (I) can be stablished by the formation of insoluble complex compounds such as ul and u(n) opper (II) oxide is red powder The water of crystallization of copper sulphate is five Explanation + + a) u u + u b) Self explanation c) uo : lack d) uso 4.5H O Q. No. 40 Zinc (II) ion on reaction with NaOH first give a white precipitate which dissolves in excess of NaOH due to the formation of : ZnO Zn(OH) [Zn(OH) 4 ] [Zn(H O) 4 ] + Explanation Zn+ NaOH Zn OH + Na + NaOH Na Zn OH 4 Q. No. 41 Mercury is a liquid at 0 0 because of : very high ionisation energy weak metallic bonds high heat hydration high heat of sublimation Explanation onceptual Q. No. 4 n element of 3d transition series shown two oxidation states x and y, differ by two units then: compounds in oxidation state x are ionic if x > y compounds in oxidation state x are ionic if x < y compounds in oxidation state y are covalent if x < y compounds in oxidation state y are covalent if y < x Explanation Lesser ox state ionic Higher ox state covalent s higher ox. state has smaller size, higher change, so higher polarizing power, so more covalent character. (fajan s rules)

10 Q. No. 43 The metal oxide which decomposes on heating is/are : ZnO l O 3 g O HgO Explanation 1 g O g + O 1 HgO Hg + O Q. No. 44 Which of the following acids attack(s) on copper and silver? dilute HNO 3 dilute Hl conc. H SO 4 aqua regia Explanation dilhno u+ 8NHO 3 3u NO + NO + 4H O 3 3 3g + 8NHO 3g NO +NO +H O dil 3g + 8NHO + O dil 3 3 ul +H O 3 dil Hl u ( dil Hl cannot oxidize g g + as its not an oxidizing agent) dil Hl g +HSO4 conc HSO4 u uso + SO + H O H SO 4 g 4 gso 4 + SO + HO qua regia dissolves copper and mercury Q. No. 45 Identify the correct statements : Iron belongs to first transition series of the periodic table The purest form of commerical iron is wrought iron nhydrous ferrous sulphate is called as yellow vitriol Iron is the most abundant transition metal Explanation a) Factual b) Factual c) Green vitriol d) Factual Q. No. 46 Which statements about mercury are correct? Hg is a liquid metal Hg forms two series of salts Hg forms no amalgam with iron and platinum nhydrous Hg does not show variable valency Explanation a) Hg is a liquid metal b) Hg+ (mercurous) Hg + (mercuric) c) Factual d) Hg + (only mercuric)

11 Q. No. 47 To an acidified dichromate solution, a pinch of Na O is added and shaken. What is observed? lue colour Orange colour changing to green opious evolution of oxygen luish green precipitate Explanation K r O H SO 4Na O ro +K SO + 4Na O+H O orange blue 4rO 6H SO r SO +6H O +HO green oranges solution turns green copious evolution of O Q. No. 48 Pick out the correct statement(s) : MnO dissolves in conc. Hl, but does not form Mn 4+ ions ecomposition of acidic KMnO 4 is not catalysed by sunlight MnO 4 is strongly oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates KMnO 4 does not act as oxidising agent in alkaline medium Explanation a) MnO 4Hl Mnl + l + H O weldon's process +4 + b) Factual itscatatysedbyhv +4 c) 3MnO 4 MnO 4 +Mn d) It acts as an ox. agent in any medium Q. No. 49 hoose correct statement(s) regarding the following reaction r O (aq) +3SO (aq) +8H r (aq)+ 3SO (aq) + 4H O ro 7 is oxidising agent SO 3 is reducing agent The oxidation number of per S atom in 3SO 3 is increase by two The oxidation number of per r atom in ro 7 is decreased by three Explanation a, b, c, d evident from the reaction Q. No. 50 ssertion : Melting point of Mn is more than that of Fe. Reason : Mn has higher number of unpaired e than Fe in atomic state. orrect nswer 4 Explanation Mn < Fe (M.P.)

12 Q. No. 51 ssertion : u + has less stable than u + but Fe 3+ is more stable than Fe +. Reason : Half filled and completely filled subshells are more stable. Explanation s u + is more stable than u + (more hydration energy), but not because of the reason specified Fe +3 >Fe + (Half filled stability) Q. No. 5 ssertion : Zn gives H gas with dil. Hl and also with dil. H SO 4. Reason : NO 3 ion is reduced in preference to hydronium ion. Explanation oth are true, but have no connection whatsoever Q. No. 53 ssertion : KMnO 4 has different equivalent weights in acid, neutral or alkaline medium. Reason : In different medium, change in oxidation number shown by manganese is altogether different. Explanation Q. No. 54 ssertion : u + is more stable than u +. Reason : Electrode potential is more important in determining stable oxidation state than electornic configuration. Explanation Self explanatory statements

13 Q. No. 55 ssertion : KMnO 4 is purple in colour to charge transfer. Reason : There is no electron present in d orbitals of manganese in. Explanation olour arises due to central metal to ligand change transfer. No connection with reason, although its correct. Q. No. 56 ssertion : ro 3 reacts with Hl to form chromyl chloride gas. Reason : hromyl chloride (ro l ) has tetrahedral shape. Explanation hromyl chloride ro l ro + Hl ro l +H O 3 Q. No. 57 ssertion : Hg is the only metal which is liquid at 0 0. Reason : It has very high I.P. and weak metallic bond. Explanation onceptual / Factual Q. No. 58 ssertion : uso 4.5H O and FeSO 4.7H O are blue and green colour compounds respectively. Reason : oth compounds have their specific colour due to phenomenon of polarisation of anion. Explanation olored due to U.P. e present in cation

14 Q. No. 60 ssertion : gno 3 reacts with KN to form white ppt. of gn. This white ppt. disappears when excess KN is added. Reason : gn decomposes to form silver carbide and evolve N gas. Explanation gno +KN gn +KNO 3 3 white KN K g N soluble Reason is totally irrelevant Instruction omprehension white substance X when heated in a test tube, produces a colourless, odourless gas leaving a residue, yellow when hot and while when cold. The residue was dissolved in dil. Hl, made alkaline with NH 4 l and NH 4 OH and H S gas was passed through it. white. ppt Y was formed. It was dissolved in dil. Hl to give Z which on treatment with K 4 [Fe(N) 6 ] gave bluish white precipitate. Q. No. 61 X is ZnO ZnSO 4. 7H O u l ZnO 3 orrect nswer 4 Explanation ZnO ZnO + O colourcless,odourlessgas X 3 yellow Hot white cold Q. No. 6 Y and Z are respectively ZnO, ZnSO 4 ZnS, Znl Znl Zn(OH) ZnO, ZnS Explanation Zn + basich S ZnS Hl Znl Qualitative analysis dirty whiteppt Q. No. 63 luish white precipitate formed is Zn [Fe(N) 6 ] K [Zn(N) 4 ] Zn 3 [Fe(N) 6 ] None of these Explanation K4 Fe N Znl 6 Zn Fe N 6 luishwhite

15 Instruction omprehension certain metal (X) is boiled in dilute HNO 3 to give a salt (Y) and an oxide of nitrogen (Z). n aqueous solution of (Y) with brine solution gives a white precipitate (P). When (Y) was treated with Na S O 3 solution a white precipitate (Q) was obtained which on standing turns to a black compound (R). Q. No. 64 Salt (Y) and the oxide of nitrogen (Z) is gno 3 + NO gno 3 + NO gno 3 + N gno 3 + NH 3 Explanation 3g 3gNO +NO+ H O X dilh NO 3 4HNO 3 3 Y Z Q. No. 65 The precipitate (Q) formed is g S g S O 3 g O g SO 3 Explanation gno +Na S O g S O +NaNO Y Q white R Stading +H O g S +H SO black 4 Q. No. 66 The compound (R) formed is g O g g S g SO 3 Explanation brine gno gl 3 10%Nacl white

What is: (a) aqua fortis, (b) aqua regia (c) Fixation of Nitrogen?

EXERCISE.1 Question 1: What is: (a) aqua fortis, (b) aqua regia (c) Fixation of Nitrogen? Solution 1: Book Name: Selina concise (a) Aqua fortis: Nitric acid is called aqua fortis. Aqua fortis means strong