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 CHAPTER 2

 
S-BLOCK ELEMENTS 
 
1. Which of the following sulphates is not soluble in water: 
(a) Sodium sulphate  (b) Potassium sulphate 
(c) Zinc sulphate    (d) Barium sulphate 

2. Chile Salt peter has the chemical formula: 
(a) NaNO3      (b) KNO3   
(c) Na2B4O7    (d) Na2CO3.H2O 

3. Which one of the following compounds when dissolved in water reacts with CO2: 
(a) Calcium chloride   (b) Sodium chloride 
(c) Calcium Sulphate   (d) Calcium hydroxide 

4. The main product of the reaction of potassium with oxygen is 
(a) KOH  (b) K2O2  (c) KO2   m(d) K2O 

5. The alkali metal whose carbonate is relatively less stable to heat and decomposes on heating, giving its oxides is:  
(a) Li  (b) Ba   (c) K   (d) Rb 

6. Which of the following compounds has a per oxide linkage: 
(a) BaO2  (b) CO2  (c) PbO2   (d) SiO2 

7. Which of the following does not belong to alkaline earth metals: 
(a) Be  (b) Mg  (c) Ra   (d) Rb 

8. Which does not belong to alkali metals: 
(a) Cs  (b) Fr  (c) Na   (d) Ca 

9. The oxides of beryllium are: 
(a) Acidic     (b) Neutral   
(c) Basic      (d) Amphoteric 

10. Nelson’s cell is used to prepare: 
(a) Sodium hydroxide  (b) Sodium carbonate 
(c) Sodium metal      (d) Sodium bicarbonate 

11. What is deposited at the cathode during the electrolysis of brine: 
(a) Na  (b) H2  (c) Cl2   (d) OH 

12. Which of the following is a rare radioactive element: 
(a) Fr  (b) Cs  (c) Ra   (d) Rb 

13. The chemical formula of Magnesite is: 
(a) MgCl2     (b) Mg (ClO3)2  
(c) MgCO3     (d) None of these 

14. Which cartbonate of alkali metals is insoluble in water: 
(a) Na2Co3  (b) K2CO3  (c) Li2CO3 (d) Cs2CO3 

15. Ga has most common oxidation state of:  
(a) +3  (b) +2  (c) +4   (d) +1 

16. Alkali metals form: 
(a) Ionic compounds .                      (b) Covalent compounds 
(c) Coordinate covalent compounds            (d) None of these 

17. Li2O is:                                (a) Orange yellow solid                      (b) White solid 
(c) Greenish solid                          (d) Pale yellow solid 

18. Melting point of pure sodium chloride is: 
(a) 600 oC (b) 775 oC (c) 750 oC  (d) 801 oC 

19. Lime (CaO) is obtained by thermal decomposition of: 
(a) Ca(OH)2 (b) CaCO3  (c) CaHCO3   (d) None 

20. The element necessary for normal “leaf” development is: 
(a) Phosphorus    (b) Sulphur   
(c) Calcium       (d) Magnesium 

21. Lime is often used as: 
(a) Reducing Agent    (b) Oxidizing Agent 
(c) Dehydrating Agent (d) Catalytic Agent 

22. Sodium metal can be stored in: 
(a) Alcohol  (b) Kerosene oil             (c) H2O      (d) All 

23. Which of the following alkali metal hydroxide is the strongest base: 
(a) LiOH  (b) NaOH  (c) KOH   (d) CsOH 

24. Washing soda has the formula: 
(a) Na2CO3.7H2O  (b) Na2CO3.10 H2O          (c) Na2CO3.3H2O  (d) Na2CO3 

25. Which halide has the highest melting point: 
(a) NaCl  (b) NaBr  (c) NaF   (d) Nal 

26. The alkali metal that reacts with nitrogen directly to form Nitride is: 
(a) Li  (b) Na  (c) K   (d) Rb 

27. The electronic configuration of metal (M) is 1s2, 2s2, 3s1. The formula mof its oxide would 
be : 
(a) MO  (b) M2O  (c) M2O3   (d) MO2 

28. An aqueous solution of sodium carbonate is alkaline because sodium carbonate is a salt 
of: 
(a) Weak acid and weak base                (b) Strong acid and weak base 
(c) Weak acid and strong base              (d) Strong acid and strong base 

29. Which of the following is a man-made element? 
(a) Ra  (b) Fr  (c) Rn   (d) Cs 

30. Dolomite has the composition 
(a) KCl.MgCl2.6H2O (b) Na3AlF6   
(c) CaCO3.MgCO3    (d) CaCl2.MgCl2.6H2O 

31. Epsom salt is: 
(a) Magnesium sulphate                     (b) Ferrous ammonium sulphate 
(c) Magnesium ammonium phosphate              (d) Calcium sulphate 

32. Plaster of Paris is a hydrate of: 
(a) BaSO4  (b) CaSO4 (c) MgSO4   (d) ZnSO4 

33. Which of the following on heating above 100C gives plaster of Paris: 
(a) Borax  (b) Gypsum (c) Alum   (d) Calomel 

34. On heating quick lime with coke in an electric furnace, we get: 
(a) Ca and CO2 (b) CaCO3  (c) Ca+CO (d) CaC2 

35. The substance not likely to contain CaCO3 is : 
(a) Dolomite    (b) Marble   
(c) Gypsum      (d) Sea shells 

36.  The oxide of Beryllium is: 
(a) Acidic       (b) Basic   
(c) Amphoteric   (d) None of these 

37. Point out the ore of potassium:         (a) Dolomite     (b) Cryolite   
(c) Bauxite      (d) Carnallite 

38. Dolomite is an ore of:                 (a) Strontium     (b) Magnesium   
(c) Barium        (d) Potassium 

39. Which is not an alkali metal? 
(a) Francium  (b) Cesium                       (c) Rubidium  (d) Radium 

40. Chile salt peter has the chemical formula: 
 (a) NaNO3       (b) KNO3   
 (c) Na2Br4O7    (d) Na2CO3 .H2O 

41. The milk of magnesia is used for the treatment of: 
 (a) Acidity      (b) Basicity   
(c) Rancidity     (d) Jaundice  

42. Cement contains gypsum:       
 (a)  3%  (b)  2%  (c)  0.2%   (d)  0.3% 

43.  Dolomite is:                      
(a)  CaCO3   (b)  MgCO3.CaCO3              (c)  MgCO3   (d)  Na2CO3 

44. Chemical formula of Magnesite is:       
(a) CaMg3(SiO3)4 (b) MgCO3                (c) MgSO4        (d) MgCl2 

45. Which one does not belong to alkaline earth metals?      
 
(a) Be  (b)  Ra  (c)  Ba   (d)  Rn 

46. The substance deposited at the cathode during electrolysis of brine in diaphragm cell:  
 
 (a)  Na  (b)  H2  (c)  Cl2   (d)  O2 

47. The ore CaSO4.2H2O has general name:       
 (a)  Gypsum      (b)  Dolomite 
 (c)  Calcite     (d)  Epsom salt 

48. The only alkaline earth metal which forms peroxide is:    
(a)  Beryllium (b)  Magnesium              (c)  Calcium   (d)  Barium 

49. The sulphate compound insoluble in water is:     
 (a)  Barium sulphate    (b) sodium sulphate 
 (c)  Potassium sulphate (d)  Zinc sulphate 

50. CaCl2 is added to NaCl in Down’s cell to:     
(a)  Decrease solubility                  (b)  Decrease dissociation 
(c)  Decrease Melting point                (d)  Decrease conductivity