#### OCTOBER MONTHLY TEST

11th Standard

Reg.No. :
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Chemistry

Time : 02:30:00 Hrs
Total Marks : 165

PART-A

15 x 1 = 15
1. For alkali metals, which one of the following trends is incorrect?

(a)

Hydration energy: Li > Na > K > Rb

(b)

Ionisation energy: Li > Na > K > Rb

(c)

Density: Li < Na < K < Rb

(d)

Atomic size: Li < Na < K < Rb

2. Which of the following statements is in correct?

(a)

Li+ has minimum degree of hydration among alkali metal cations

(b)

The oxidation state of K in KO2 is +1

(c)

Sodium is used to make Na / Pb alloy

(d)

MgSO4 is readily soluble in water

3. Which of the following compounds will not evolve H2 gas on reaction with alkali metals?

(a)

ethanoic acid

(b)

ethanol

(c)

phenol

(d)

none of these

4. Which of the following has the highest tendency to give the reaction $M_{g}^{+}\xrightarrow[Medium]{Aqueous}M_{aq}^{+}$

(a)

Na

(b)

Li

(c)

Rb

(d)

K

5. sodium is stored in

(a)

alcohol

(b)

water

(c)

kerosene

(d)

none of these

6. Match the flame colours of the alkali and alkaline earth metal salts in the bunsen burner

 (P) Sodium (1) Brick red (q) Calcium (2) Yellow (r) Barium (3) Violet (s) Strontium (4) Apple green (t) Cesium (5) Crimsonred (u) Potassium (6) Blue
(a)

p-2, q-1, r-4, s-5, t-6, u-3

(b)

p-1, q-2, r-4, s-5, t-6, u-3

(c)

p-4, q-1, r-2, s-3, t-5, u-6

(d)

p-6, q-1, r-2, s-3, t-5, u-4

7. Assertion : BeSO4 is soluble in water while BaSO4 is not
Reason : Hydration energy decreases down the group from Be to Ba and lattice energy remains almost constant.

(a)

both assertion and reason are true and reason is the correct explanation of assertion

(b)

both assertion and reason are true but reason is not the correct explanation of assertion

(c)

assertion is true but reason is false

(d)

both assertion and reason are false.

8. Among the following the least thermally stable is

(a)

K2CO3

(b)

Na2CO3

(c)

BaCO3

(d)

Li2CO3

9. Half life of francium is _______

(a)

12.3 years

(b)

12.3 mins

(c)

21 years

(d)

21 mins

10. The hydration enthalpies of alkali metal ions decreases in ______ order.

(a)

Li+ > Na+ > K+ > Rb+ > Cs+

(b)

Cs+ > Rb+ > K+ > Na+ > Li+​​​​​​​

(c)

Li+ > Rb+ > K+ > Na+ > Cs+​​​​​​​

(d)

Rb+ > Cs+ > K+ > Na+ > Li+

11. The order of decreasing ionisation enthalpy in alkali metals is

(a)

Na > Li > K > Rb

(b)

Rb < Na < K < L

(c)

Li > Na > K > Rb

(d)

K < Li < Na < Rb

12. The correct increasing order of density of alkali metal is

(a)

Li < K < Na < Rb < Cs

(b)

Li < Na > K < Rb < Cs

(c)

K < Li < Rb < Na

(d)

Cs < Rb < K < Na < Li

13. Which of the following oxides is the most basic in nature?

(a)

Na2O

(b)

BeO

(c)

Li2O

(d)

H2O

14. Match the list I with List II and select the correct answer using. the code given below the lists.

List I List II
A Ba 1 Crimson red
B Ca 2 Lilac
C Sr 3 Apple green
D K 4 Brick red
(a)
 A B C D 1 3 2 4
(b)
 A B C D 4 3 1 2
(c)
 A B C D 3 4 1 2
(d)
 A B C D 2 1 4 3
15. Quicklime is _________

(a)

CaCO3

(b)

CaO

(c)

Ca(OH)2

(d)

CaSiO3

16. PART - B

20 x 2 = 40
17. Explain what is meant by efflerescence.

18. Give the systematic names for the following
(i) milk of magnesia
(ii) lye
(iii) lime
(iv) Caustic potash
(v) washing soda
(vi) soda ash
(vii) trona

19. Substantiate lithium fluoride has the lowest solubility among group one metal fluorides.

20. Mention the uses of plaster of paris

21. Beryllium halides are Covalent whereas magnesium halides are ionic why?

22. Write balanced chemical equation for the following processes
(a) heating calcium in oxygen
(b) heating calcium carbonate
(c) evaporating a solution of calcium hydrogen carbonate
(d) heating calcium oxide with carbon

23. How is plaster of paris prepared?

24. Give the uses of gypsum

25. How is sodium bicarbonate prepared?

26. Discuss the biological importance of sodium and potassium.

27. What is the cause for diagonal relationship between beryllium and aluminium?

28. How does (i) solubility, (ii) thermal stability, (iii) basic character hydroxides of group 2 elements very down the group.

29. Arrange the following as indicated.
(i) BeSO4, MgSO4 CaSO4, SrSO4 and BaSO4 in the increasing order of solubility.
(ii) Be (NO3)2,  Mg(NO3)2 , Ca(NO3)2 , Sr(NO3)2 , Ba(NO3)2 < Ba(NO3)2 in decreasing order of forming hydrated salts.

30. Give equations for the reaction of CaO with
(i) H2O
(ii) CO2
(iii) SiO2
(iv) P4O10.

31. What is slaked lime? How is it produced?

32. Explain the term 'desert rose'.

33. What is 'dead burnt plaster'? What is use?

34. Mention the uses of quick lime

35. Beryllium and magnesium do not give colour to flame whereas other alkaline earth metals do so. Why?

36. What is the effect of heat on the following compounds (Give equations for the reactions)?
(i) CaCO3 (ii) CaSO4.2H2O

37. PART - C

20 x 3 = 60
38. Why sodium hydroxide is much more water soluble than chloride?

39. Write the chemical equations for the reactions involved in solvay process of preparation of sodium carbonate.

40. An alkali metal (x) forms a hydrated sulphate, X2SO4•10H2O. Is the metal more likely to be sodium (or) potassium.

41. Why alkaline earth metals are harder than alkali metals.

42. Which would you expect to have a higher melting point magnesium oxide or magnesium fluoride? Explain your reasoning.

43. Alkali metals have low melting and boiling point.Density of alkali metals is very low. Give reason.

44. List down the uses of washing soda

45. What is meant by 'diagonal relationship' in periodic table? Why is it so?

46. Why is the behaviour of beryllium is different from the other elements of the same group?

47. Be and Mg do not give colour to flame whereas other alkaline earth metals do so. Why?

48. Complete and balance the following equations for the reactions given between
(i) Slaked lime + CO2 + H2O
(ii) Quick lime + CO2
(iii) Slaked lime + CO2
(iv) Be(OH)2 + HCl + H2O

49. How is bleaching powder prepared ?

50. How would you explain the following observation? BeO is almost insoluble but BeSO4 is soluble in water.

51. Explain why?
(i) The ionic character of hydrides of alkali metals increase from Li to Cs.
(ii) The stability of hydrides decrease down the group.
(iii) Hydrides behave as strong reducing agents.

52. Explain the solvay process of manufacturing sodium carbonate.

53. Explain the Castner-Kellner process of manufacturing sodium hydroxide.

54. Although IE1 values of alkaline earth metals are higher than that of alkali metals the IE2 values of alkaline earth metals are much smaller than alkali metals. Explain.

55. How alkali metals react with liquid ammonia?

56. Be(OH)2 is amphoteric in nature. Prove it

57. Draw the structure of BeCl2 in different physical state

58. PART - D

10 x 5 = 50
59. Discuss briefly the similarities between beryllium and aluminium.

60. Alkaline earth metal (A), belongs to 3rd period reacts with oxygen and nitrogen to form compound (B) and (C) respectively. It undergo metal displacement reaction with AgNO3 solution to form compound (D).

61. Explain the important common features of Group 2 elements.

62. Describe briefly the biological Importance of Calcium and magnesium

63. Compare the properties of beryllium with other elements of the same group.

64. An element belongs to group 1 and period 3 reacts with chlorine gas to form A. (A) reacts with ammonium bicarbonate to give compounds (B) and (C). Compound (B) is then heated to give compound (D). Identify A, B, C and D and write the respective equations.

65. An element A belonging to group 2 and period 2 reacts with chlorine at an elevated temperature to give compound (B) compound B combines with LiAIH4 to form compound (C). Which is an hydride identify A, B, and C?

66. Discuss the anomalous behaviour of beryllium.

67. Describe the biological importance of sodium and potassium.

68. Distinguish between alkali metals and alkaline earth metals.