1. Which of the following statements regarding alkali metals is not correct?

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1 1. Which of the following statements regarding alkali metals is not correct? Alkali metals are soft and have comparatively low melting points as compared to other metals Francium is a radioactive element Alkali metals are strongly reducing agents (d ) Sodium is used in the photoelectric cells. 2. Which of the following statement is not correct? Lithium forms oxide on burning in air Sodium forms peroxide on burning in air Potassium forms peroxide on burning in air Rubidium forms superoxide on burning in air. 3. Which of the following orders regarding the melting point of alkali chlorides is true? LiCl < NaCl < KCl < RbCl LiCl > NaCl > KCl > RbCl LiCl < NaCl > KCl > RbCl LiCl > NaCl < KCl < RbCl. 4. Lithium exhibits diagonal relationship with Magnesium Calcium Aluminium Strontium. 5. Sodium is not ordinarily observed in the +2 oxidation state because of its High first ionization potential High second ionization potential High ionic radius High electronegativity. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

2 6. When rubidium is reacted with oxygen, the compound formed is RbO Rb 2 O Rb 2 O 2 RbO The metallic luster exhibited by sodium is explained by the presence of Na + ions Conduction electrons Free protons A body-centred cubic lattice. 8. Ionic radii of alkali metal ions in water are in the order Li + > Na + > K + > Rb + Li + < Na + < K + < Rb + Li + > Na + > K + < Rb + Li + > Na + < K + < Rb Which of the following ions has the highest reduction potential? Li + Na + K + Rb +. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

3 10. Which of the following metals has the maximum enthalpy of sublimation? Li Na K Rb. 11. The number of water molecules of crystallization in sodium carbonate is Which of the following is known as Indian salt petre? LiNO 3 NaNO 3 KNO 3 RbNO Which of the following is not treated as primary standard in the volumetric analysis? Sodium carbonate Sodium thiosulphate Potassium dichromate Sodium chloride. 14. Which of the following is not the minerals of potassium Chile saltpeter Carnallite Kainite Potassium feldspar. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

4 15. Which of the following chemical equations is not actually observed? 2M + 2H 2 O 2MOH + H 2 ; where M is Na or K 2M + 2NH 3 2MNH 2 + H 2 ; where M is Na or K. 16. Which of the following represents the composition of carnallite mineral? KCl MgCl 2 6H 2 O K 2 SO 4 MgSO 4 MgCl 2 6H 2 O KNO 3 K 2 O Al 2 O 3 6SiO Solvay process is used for the manufacture of Na 2 CO 3 10H 2 O K 2 CO 3 NaOH Na 2 O Which of the following is known as baking soda? Na 2 CO 3 10H 2 O NaHCO 3 K 2 CO 3 NaOH. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

5 19. Castner-Kelllner cell is used for the production of NaOH Na 2 CO 3 NaHCO 3 NaCl. 20. Which of the following statements is not correct? The main raw material required in Solvay process are sodium chloride and ammonium chloride NaHCO 3 is less soluble in water as compared to NH 4 Cl The byproduct in Solvay process is calcium chloride Na 2 CO 3 10H 2 O is commonly known as washing soda or soda ash. 21. The alkali metals are low melting. Which of the following alkali metal is expected to melt if the room temperature rises to 30 C? Na K Rb Cs 22. Alkali metals react with water vigorously to form hydroxides and dihydrogen. Which of the following alkali metals reacts with water least vigorously? Li Na K Cs 23. The reducing power of a metal depends on various factors. Suggest the factor which makes Li, the strongest reducing agent in aqueous solution. Sublimation enthalpy Ionisation enthalpy Hydration enthalpy Electron-gain enthalpy AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

6 24. Metal carbonates decompose on heating to give metal oxide and carbon dioxide. Which of the metal carbonates is most stable thermally? MgCO3 CaCO3 SrCO3 BaCO3 25. Which of the carbonates given below is unstable in air and is kept in CO2 atmosphere to avoid decomposition. BeCO3 MgCO3 CaCO3 BaCO3 26. Metals form basic hydroxides. Which of the following metal hydroxide is the least basic? Mg(OH)2 Ca(OH)2 Sr(OH)2 Ba(OH)2 27. Some of the Group 2 metal halides are covalent and soluble in organic solvents. Among the following metal halides, the one which is soluble in ethanol is BeCl2 MgCl2 CaCl2 SrCl2 28. The order of decreasing ionisation enthalpy in alkali metals is Na > Li > K > Rb Rb < Na < K < Li Li > Na > K > Rb K < Li < Na < Rb AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

7 29. The solubility of metal halides depends on their nature, lattice enthalpy and hydration enthalpy of the individual ions. Amongst fluorides of alkali metals, the lowest solubility of LiF in water is due to Ionic nature of lithium fluoride High lattice enthalpy High hydration enthalpy for lithium ion. Low ionisation enthalpy of lithium atom 30. Amphoteric hydroxides react with both alkalies and acids. Which of the following Group 2 metal hydroxides is soluble in sodium hydroxide? Be(OH)2 Mg(OH)2 Ca(OH)2 Ba(OH)2 31. In the synthesis of sodium carbonate, the recovery of ammonia is done by treating NH4Cl with Ca(OH)2. The by-product obtained in this process is CaCl2 NaCl NaOH NaHCO3 32. When sodium is dissolved in liquid ammonia, a solution of deep blue colour is obtained. The colour of the solution is due to ammoniated electron sodium ion 33. By adding gypsum to cement setting time of cement becomes less. (b )s etting time of cement increases. sodium amide ammoniated sodium ion colour of cement becomes light. shining surface is obtained. 34. Dead burnt plaster is AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

8 35. Suspension of slaked lime in water is known as lime water milk of lime quick lime aqueous solution of slaked lime 36. Which of the following elements does not form hydride by direct heating with dihydrogen? Be Mg Sr Ba 37. The formula of soda ash is Na2 CO3.10H2O Na2CO3.H2O Na2CO3.2H2O Na2CO3 38. A substance which gives brick red flame and breaks down on heating to give oxygen and a brown gas is Magnesium nitrate Barium nitrate Calcium nitrate 39. Which of the following statements is true about Ca(OH)2? It is used in the preparation of bleaching powder It is a light blue solid Strontium nitrate It does not possess disinfectant property. It is used in the manufacture of cement. 40. A chemical A is used for the preparation of washing soda to recover ammonia. When CO2 is bubbled through an aqueous solution of A, the solution turns milky. It is used in white washing due to disinfectant nature. What is the chemical formula of A? Ca (HCO3)2 CaO Ca(OH)2 CaCO3 AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

9 (41) Which of the following alkaline earth metal sulphates has hydration enthalpy higher than the lattice enthalpy? SrSO 4 MgSO 4 CaSO 4 BaSO 4 (42) A compound (A) on heating gives a colourless gas and a residue that is dissolved in water toobtain (B). Excess of CO 2 is bubbled through aqueous solution of B, (C) is formed, which is recovered in the solid form. Solid (C) on gentle heating gives back (A). The compound is... CaCO 3 K 2 CO 3 Na 2 CO 3 CaSO 2H O 4 2 (43) For alkaline metal, which of the following trends is incorrect? Hydration enthalpy : Be > Mg > Ca > Sr Second Ionization enthalpy: Be > Mg > Ca > Sr Density : Sr > Be > Mg > Ca Atomic size : Sr > Ca > Mg > Be (44) Which of the following compounds is most stable? LiCl LiI LiBr LiF (45) Flame test is not given by... Be Sr K Ca (46) The alkaline earth metals forming ionic oxides are... MgO BeO CaO and (47) The basic character of the oxides MgO, SrO, K 2 O, NiO and Cs 2 O increases in the order : MgO > SrO > K 2 O > NiO > Cs 2 O Cs 2 O < K 2 O < MgO < SrO < NiO NiO < MgO < SrO < K 2 O < Cs 2 O K 2 O < NiO < MgO < SrO < Cs 2 O (48) Which of the following are arranged in increasing order of solubilities? CaCO 3 < KHCO 3 < NaHCO 3 NaHCO 3 < KHCO 3 < CaCO 3 KHCO 3 < NaHCO 3 < CaCO 3 CaCO 3 < NaHCO 3 < KHCO 3 (49) The compound insoluble in aceticacid is... Calcium oxide Calcium oxalate Calcium carbonate Calcium hydroxide (50) Which of the following has the lowest melting point? LiCl KCl NaCl RbCl (51) The correct order of decreasing ionic character is... BeCl 2 > MgCl 2 > CaCl 2 > BaCl 2 BeCl 2 > MgCl 2 > BaCl 2 > CaCl 2 BeCl 2 > BaCl 2 > MgCl 2 > CaCl 2 BaCl 2 > CaCl 2 > MgCl 2 > BeCl 2 AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

10 (52) The highest lattice energy corresponds to... MgO CaO SrO BaO (53) How many of the following s -block elements do not give characteristic colours in the flame test?li, Be, Ca, Ba, Sr, Mg, Na, K, Ba (54) How many of the following sulphates of metals dissolve in the water? SrSO 4, K 2 SO 4, BeSO 4, Li 2 SO 4, MgSO 4, BaSO 4, Na 2 SO 4, CaSO 4, Rb 2 SO (55) How many of the following hydroxides is/are amphoteric in character? CsOH, LiOH, Ca(OH) 2, Be(OH) 2, Mg(OH) 2, Sr(OH) 2, Ba(OH) 2, KOH, NaOH (56) Out of Li, Na, K, Rb and Cs how many of them directly form superoxides on heating with oxygen? (57) How many of the following metals when heated in an atmosphere of N 2 gas form nitrides? Li, Na, K, Rb, Cs, Mg, Ca, Sr, Ba (58) Which of the following is not correct for workfunction of Na + ions in human body? An important role in nerve signal transmission. Control of flow of water between cell membrane. For transport of sugar and amino acid in cell. They activate the enzyme. (59) Which of the following is not correct? 2Li O ¾¾¾ Li O + 2Li 2K O ¾¾¾ K O + 2K 673k heat heat 2 673k Na O ¾¾ heat 673k ¾ Na O + 2Na ¾¾ heat ¾ 2 2 (60) Which of the following has maximum lattice energy? 2Rb O 673k Rb O + 2Rb Li 2 O Na 2 O MgO BaO (61) Which of the following statements is/are correct for when alkali metals are dissolved in liquid ammonia. We get... A blue solution in case of dilute alkali metal ammonia solution. If we increase cocentration of metal in ammonia then the blue colour starts changing and finally changes to that of bronze colour. The blue colour of the solution of alkali metal in liquid ammonia is due to excitation of free ammoniated electrons to higher energy levels. All the above are correct. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

11 (62) Which of the following pairs of elements possess diagonal relationship? Li and Mg Li and Al Na and Mg Cs and Ba (63) Fill in the blanks with suitable option. The important ingredients of potland cement are dicalcium silicate %, tricalcium silicate... % and tricalcium aluminate % respectively. 26 %, 51%, 11% 51%, 26%, 11% 11%, 51%, 26% 26%, 11%, 51% (64) A sample of portaland cement contain 23% SiO 2, 3% Al 2 O 3 and 2% Fe 2 O 3 then what would be its silica module (n)? (65) For a good quality of cement, the ratio of silica (SiO 2 ) and alumina (Al 2 O 3 ) must be between... 3 to to 4 6 to to 5.5 (66) Chloro phyll and heamoglobin are complex of and respectivelly.. Mg 2+ and Ca 2+ Na + and K + Mg 2+ and Fe 2+ Cl and Fe 2+ (67) Which of the following is the component of most of the kidney stones? (COO) 2 Ca (COONa) 2 (COO) 2 Ba (COO) 2 Mg (68) Which of the following metal ions plays an important role in muscle contraction? K + Mg 2+ Na + Ca 2+ (69) White enamel of our teeth is... Ca 3 (PO 4 ) 2 CaCl 2 CaF 2 CaBr 2 (70) Two mole of magnesium nitride on reacting with an excess of water gives : One mole of ammonia Four moles of ammonia Two moles of nitric acid Three moles of ammonia (71) Which of the following metal is used in windows of X - ray tubes? Be Mg Ba Al (72) Which of the following is not a Mg ore? Magnesite Gypsum Dolomite Carnalite (73) The difference of water molecules in gypsum and plaster of paris is AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

12 (74) Which of the following exists in polymeric form? AlCl 3 SiC BeCl 2 B 2 H 6 (75) The electronic cofiguration of metal M is ls 2 2s 2 2p 6 3s 2. The formula of its oxide would be... MO M 2 O M 2 O 3 MO 2 (76) The formula of carnalliteis... KCl MgCl 2 2H 2 O K2O Al2O3 6H2O KCl g MgCl2 g 6H2O Na2B4O7 10H2O (77) When NaOH is made, the gas released at the cathode is... Cl 2 H 2 O 2 H 2 O (78) Choose proper option for matching column - I and column - II Column - I (A) NaOH (B) Na 2 CO 3 (C) Liquid Na (D) Caesium A-R, B-S, C-Q, D-P A-Q, B-P, C-R, D-S Column - II (P) Photo electric cells (Q) Coolant in nuclear reactors (R) SO 2 absorber (S) Detergent A-P, B-Q, C-R, D-S A-S, B-Q, C-P, D-R (79) In the electrolytic separation of Li, KCl is added to LiCl.. To increase the conductivity of LiCl To lower the fusion temperature of the mixure To decrease the conductivity of LiCl Both and (80) Molecular formula of Glauber s salt is... MgSO 4 7H 2 O FeSO 4 7H 2 O CuSO 4 5H 2 O Na 2 SO 4 10H 2 O (81) The name Blue John is given to which of the following compounds. CaH 2 CaF 2 Ca 3 (PO 4 ) 2 CaO (82) The wire of flash bulb is made of... Mg Cu Ba Ag (83) 30 gm of Mg and 30 gm of O 2 are reacted and the residual mixure contains gm of MgO only 40 gm of MgO and 20 gm of O 2 45 gm of MgO and 15 gm of O 2 50 gm of MgO and 10 gm of O 2 AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

13 (84) Which of the following is not correct? 4LiNO 2NaNO 2(s) + O 2(g) 3(s) 2Li 2 O (s) + 4NO 2(s) + O 2(g) 2NaNO 3(s) The oxides Li 2 O and MgO do not give super oxides by combining with more oxygen. Lithium hydrogen carbonate is obtained in solid form. (85) The number and type of bonds between two carbon atoms in calcium carbides are... one sigma, one pi. two sigma, one pi. one sigma, two pi. two sigma, two pi (86) Which of the following salts are composed of isoelectronic cations and anions? NaCl MgF 2 CaS and both (87) Which are correct statements for Be and Al? Both are rendered passive by con.hno 3 Both have sp - hybridization in their compounds. Both form acidic oxides Both form hydrides (88) Identify the correct statement? Gypsum contains a lower percentage of calcium than plaster of paris Gypsum is obtained by heating plaster of paris Plaster of paris can be obtained by hydration of gypsum Plaster of paris is obtained by partial oxidation of gypsum. (89) Which of the following metal is used in the test of elements in organic compounds by Lassigne test? Li Na K Rb (90) The setting time of dicalcium silicates is 28 days 1 year 1 week 24 hour Assertion - Reason type Questions The questions given below contains statement - 1 (Assertion) and statement - 2 (Reason) Eachquestion has four choices,, and out of which only one is correct. Choose the correctoption as under. Statement -1 is true, statement - 2 is true Statement - 2 is a correct explanation for statement - 1 Statement - 1 is true, statement - 2 is true; Statement - 2 is not a correct explanation for statement - 1 Statement - 1 is true, statement - 2 is false Statement - 1 is false, statement - 2 is true. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

14 (91) Statement-1 Alkali metals dissolve in ammonia to give blue solutions. Statement-2 Alkali metals in liquid ammonia give solvated species of the type [M(NH 3) X] + (92) Statement-1 Sodium metal is softer than potassium metalstatement-2 Metalic bonding in Potassium is weaker than insodium. (93) Statement-1 Be(OH) 2 is solublein HCl and NaOH Statement-2 Be(OH) 2 is amphoteric in nature (94) Statement-1 Be Forrns [BeF 4 ] 2 but Al forrms [AlF 6 ] 3 Statement-2 Be doesnot have d orbitals in the Valence shell but Al has. (95) Statement - 1 Li CO and Na CO are therally unstable Statement - 2 Both the carbonates are salts of large cations and large anions. (96) Statement - 1 Metallic character of alkali metals increases on going down a group from top tobottom. Statement - 2 Ionisation enthalpy of alkali metals increases on going down from top to bottom. (97) Statement - 1 Superoxides of alkali metals are diamagnetic. Statement - 2 Superoxides contain the ion O 2 which has one unpaired electron. (98) Statement - 1 Alkali metals donot impart colour to the flame. Statement - 2 Their ionization enthalpies are very low. (99) Statement - 1 Sodium cannot be obtained by chemical reduction of its ore. Statement - 2 Sodium is one of the strongest reducing agent. (100) Statement - 1 Beryllium hydroxide becomes soluble in excess alkali forming beryllate ion [Be(OH) 4 ] 2- Statement - 2 Beryllium ion has greater tendency to form complexes. AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB

15 ANSWER 1. d 2. c 3. c 4. a 5. b 6. b 7. b 8. a 9. a 10. a 11. b 12. b 13. c 14. a 15.b 16. a 17. a 18. b 19. a 20. A 21d 22 a 23 c 24 d 25 a 26 a 27 a 28 c 29b 30a 31 a 32a 33b 34a 35c 36a 37 d 38 b 39a 40c (55) a (70) c (85) b (100) b (41) b (56) c (71) a (86) d (42) a (57) b (72) b (87) a (43) b (58) d (73) d (88) a (44) d (59) a (74) c (89) b (45) a (60) c (75) a (90) a (46) d (61) d (76) c (91) b (47) c (62) a (77) b (92) d (48) d (63) a (78) a (93) a (49) c (64) d (79) d (94) a (50) a (65) b (80) d (95) c (51) a (66) c (81) b (96) c (52) a (67) a (82) a (97) d (53) c (68) d (83) d (98) d (54) a (69) c (84) d (99) a AIIMS,CBSE,AIPMT, AFMC,Bio.Tech & PMT, Contact : , Mail at :- ibiokaare@gmail.com,,compiled by AKB