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Question Bank No: 4

1. The edge of a F.C.C unit cell is 508 pm. If the radius of the cation is 110m, the radius of anion is

a)		110 pm
b)		144 pm
c)		618 pm
d)		398 pm

2. Super conductors are derived from compounds of

a)		P-block elements
b)		Lanthanides
c)		actinides
d)		transition elements

3. Among solids, the highest melting point is exhibited by

a)		covalent solids
b)		ionic solids
c)		Pseudo solids
d)		molecular solids

4. An ${AB}_{2}$ type of structure is present in

a)		NaCl
b)		$N_{2} O$
c)		${Al}_{2} O_{3}$
d)		${CaF}_{2}$

5. In a crystal structure of $NaCl$ , the arrangement of ${Cl}^{-}$ ons is

a)		fcc
b)		both fcc and bcc
c)		bcc
d)		none of these

6. The existence of a substance in more than one solid modifications is known as

a)		Isomorphis
b)		Polymorphis
c)		Amorsphism
d)		none of these

7. Which of the following is a pseudo solid?

a)		${CaF}_{2}$
b)		glass
c)		$NaCl$
d)		All

8. which of the following adopts normal spinal structure?

a)		CsCl
b)		${MgAl}_{2} O_{4}$
c)		FeO
d)		${CaF}_{2}$

9. Which of the following defect lowers the density of the crystal?

a)		Frenkel
b)		Schottky
c)		Edge dislocation
d)		constitution of F centres

10. A binary solid ( $A^{+} B^{-}) has a Zinc$ blende structure with B ions constituting the lattice and $A^{+} ions$ occupying 25% tetrahedral holes. The formula of solid is

a)		AB
b)		$A_{2} B$
c)		${AB}_{2}$
d)		${AB}_{4}$

11. The unit of rate constant for a zero order reaction is

a)		litre $\sec^{- 1}$
b)		litre ${mol}^{- 1} \sec^{- 1}$
c)		$mol {litre}^{- 1} \sec^{- 1}$
d)		$mol \sec^{- 1}$

12. The effect of a catalyst in a chemical reaction is to change the

a)		Activation energy
b)		Equilibrium concentration
c)		Heat of reaction
d)		Final products

13. The rate of reaction A+B $⟶$ products is given by the equation r=K[A][B]. if B is taken inlarge excess, the order of the reaction would be

a)		2
b)		1
c)		0
d)		unpredictable

14. For a first order reaction $t_{\frac{1}{2}}$ $is$ independent of

a)		Initial concentration
b)		cube root of initial concentration
c)		First power of final concentration
d)		square root of final concentration

15. Given t $\frac{1}{2} = 3 hr .$ How many gram of a substance will remain after 18th hour from 300gram of a substance

a)		4.6g
b)		5.6g
c)		9.2g
d)		6.4g

16. $t_{\frac{1}{2}} of a$ reaction is found to be inversely propoional to the cube of initial concentration. The order of reaction is

a)		4
b)		3
c)		5
d)		2

17. The rate of reaction is doubled for $10^{0}$ rise in temperature. The increase in the reaction rate as a result of temperature rise from $10^{0} to 100^{0} is$

a)		112
b)		512
c)		1400
d)		614

18. For the reaction, $CO (g) + \frac{1}{2} O_{2} (g) \overset{}{⇌} {CO}_{2} (g), {\frac{K_{p}}{K_{c}} is}_{}$

a)		RT
b)		$(RT)^{- 1}$
c)		$(RT)^{- 1 / 2}$
d)		$(RT)^{1 / 2}$

19. The rate of forward reaction is two times that of the reverse reaction at a given temperature and identical concentration, K equilibrium is

a)		0.5
b)		1.5
c)		2.5
d)		2.0

20. The $pH$ of an aqueous solution is 6. The $[{OH}^{-}]$ of the solution will be

a)		$10^{- 8} M$
b)		$10^{- 6} M$
c)		$10^{- 7} M$
d)		$10^{8} M$

21. The pH of a $10^{- 8} M$ solution of HCl in water is

a)		8
b)		-8
c)		Between 7 an 8
d)		Between 6 and 7

22. In decimolar solution, ${CH}_{3} COOH$ acid is ionised to the extent of 1.3% if log 1.3 = 0.11, What is pH of the solution?

a)		3.89
b)		2.89
c)		4.89
d)		unpredictable

23. An aqueous solution of ${CuSO}_{4}$ is

a)		acidic
b)		basic
c)		neutral
d)		amphoteric

24. At $80^{0},$ pure distilled water has $[H_{3} O^{+}]$ = $1 \times 10^{- 6} mol L^{- 1},$ the value if Kw at this temperature will be

a)		$1 \times 10^{- 8}$
b)		$1 \times 10^{- 12}$
c)		$1 \times 10^{- 14}$
d)		$1 \times 10^{- 6}$

25. The conjugate base of ${HPO}_{4}^{2 -}$ is

a)		${PO}_{4}^{3 -}$
b)		$H_{2} {PO}_{4}^{-}$
c)		$H_{3} {PO}_{4}$
d)		$H_{3} {PO}_{3}$

26. Which of the following on reaction with $H_{2} S$ does not produce metallic sulphide?

a)		${CdCl}_{2}$
b)		${ZnCl}_{2}$
c)		${COCl}_{2}$
d)		${CuCl}_{2}$

27. Identify the indicator used to titrate ${Na}_{2} {CO}_{3}$ with HCl

a)		Phenolphthalein
b)		Dilute $H_{2} {SO}_{4}$
c)		Methyl Orange
d)		None

28. At $25^{0} C$ the pH of a solution containing 0.1M Sodium acetate and 0.03 M acetic acid is ( ${pK}_{a})$ of acetic acid = 4.57)

a)		3.24
b)		4.59
c)		5.09
d)		6.67

29. The solubility of AgCl in 0.2 M $NaCl$ is ( $K_{sp} AgCl = 1.8 \times 10^{- 10})$

a)		$1.8 \times 10^{- 11} M$
b)		$9 \times 10^{- 10} M$
c)		$6.5 \times 10^{- 12} M$
d)		$5.6 \times 10^{- 11} M$

30. The one that is a good conductor of electricity in the following list of solids is

a)		Sodium Chloride
b)		Graphite
c)		Diamond
d)		Sulphur

31. Electrolysis involves oxidation and reduction respectively at

a)		Anode and Cathode
b)		Cathode and Anode
c)		At both the electrodes
d)		None of the above

32. Which of the substances $Na, Hg, S, Pt$ and Graphite can be used as electrodes in electrolytic cells having aqueous solutions?

a)		Na, Pt and Graphite
b)		Na and Hg
c)		Pt and Graphite only
d)		Na and S only

33. The reference Calomel electrode is made from which of the following

a)		${ZnCl}_{2}$
b)		${CuSO}_{4}$
c)		${Hg}_{2} {Cl}_{2}$
d)		${HgCl}_{2}$

34. The standard ${E^{0}}_{Red}$ values of A, B, C are 0.68 V, -2.54 V, -0.50 V respectively. The order of their reducing power is

a)		A > B > C
b)		A > C > B
c)		C > B > A
d)		B > C > A

35. The resistance of $1 N$ solution of acetic acid is 250 ohm, when measured in a cell of cell constant $1.15 {cm}^{- 1} .$ The equivalent conductance of 1N acetic acid is

a)		4.6
b)		9.2
c)		18.4
d)		0.023

36. In electrorefining of copper a minor percentage of gold accumulates in

a)		Anode mud
b)		Cathode mud
c)		Electrolyte
d)		Cathode

37. Chorine cannot displace

a)		Fluorine from $NaF$
b)		Iodine from NaI
c)		Bromine from NaBr
d)		None of these

38. The equivalent conductance of NaCl, HCl and $C_{2} H_{5} COONa$ at infinite dilution are 126.45, 426.16 and 91 ${ohm}^{- 1} {cm}^{2} res$ pectively. The equivalent conductance of $C_{2} H_{5} COOH is$

a)		201.28
b)		390.71
c)		698.28
d)		540.48

39. Prevention of corrosion of iron by Zn coating is called

a)		Galvanization
b)		Cathodic protection
c)		Electrolysis
d)		Photoelectrolysis

40. In the cell reaction, $Cu (s) + 2 {Ag}^{+} (aq) \to {Cu}^{2 +} (aq) + 2 Ag (s); E^{0} cell = 0.46 V .$ By doubling the concentration of ${Cu}^{2 +}, E_{Cell} is$

a)		doubled
b)		halved
c)		unchanged
d)		decreases by small fraction

41. The specific conductance of 0.1M NaCl solution is 1.06 $\times 10^{- 2} {ohm}^{- 1} {cm}^{- 1} .$ Its molar conductance is

a)		$1.06 \times 10^{2}$
b)		$1.06 \times 10^{3}$
c)		$1.06 \times 10^{4}$
d)		53

42. Calculate the amount of charge flowing in two minutes in a wire of resistance 10 $Ω$ when a potential difference of 20 V is applied

a)		120 C
b)		240 C
c)		20 C
d)		4 C

43. For the reactions, C+ $O_{2} \to {CO}_{2};$ $Δ H = - 393 kJ,$ 2Zn+ $O_{2} \to 2 ZnO; Δ H = - 412 kJ$

a)		Carbon can oxidise zinc
b)		Oxidation of carbon is not possible
c)		Oxidation of Zn is not feasible
d)		Zn can oxidise Carbon

44. Which of the following reaction is possible at the Anode?

a)		$2 {Cr}^{3 +} + 7 H_{2} O \to {Cr}_{2} O_{7}^{2 -} + 14 H^{+}$
b)		$F_{2} \to 2 F^{-}$
c)		$\frac{1}{2} O_{2} + 2 H^{+} \to H_{2} O$
d)		None of these

45. Conductivity (unit : S) is directly proportional to the area of the vessel and the concentration of the solution in it and is inversely proportional to the length of the vessel, then the unit of constant of proportionality is

a)		S m ${mol}^{- 1}$
b)		$S m^{2} {mol}^{- 1}$
c)		$S^{- 2} m^{2} mol$
d)		$S^{2} m^{2} {mol}^{- 2}$

46. At cathode, the electrolysis of aqueous ${Na}_{2} {SO}_{4} gives$

a)		Na
b)		$H_{2}$
c)		${SO}_{3}$
d)		${SO}_{2}$

47. Which of the following is a Lewis acid?

a)		${Cl}^{-}$
b)		${NH}_{3}$
c)		${BF}_{3}$
d)		$C_{2} H_{5} OH$

48. A smuggler could not carry gold by chemically depositing iron on the gold surface since

a)		gold is denser
b)		iron rusts
c)		gold has higher reduction potential than iron
d)		gold has lower reduction potential than iron

49. Corrosion is basically a

a)		altered reaction in presence of $H_{2} O$
b)		electrochemical phenomenon
c)		interaction
d)		union between two light metals and a heavy metal

50. ${Zn}^{2 +} (aq) + 2 e^{-} \to Zn (s),$ this is

a)		oxidation
b)		reduction
c)		redox reaction
d)		none of these