Top of Pyramid - Test #48

1.

The conjugate base of H₃BO₃ is:
1. $B (OH)_{4}^{-}$
2. $H_{2} {BO}_{3}^{-}$
3. ${HBO}_{3}^{2 -}$
4. $H_{4} {BO}_{3}^{+}$

2.

Given a system: $A (s) \overset{}{⇌} 2 B (g) + 3 C (g) .$
If the concentration of C at eqilibrium is increased by a factor 2, it will cause the eqilibrium concentration of B to change to:
1. two times of its original value
2. one half of its original value
3. 2 $\sqrt{2}$ times of its original value
4. $\frac{1}{2 \sqrt{2}}$ times of its original value

3.

Ionisation constant of CH₃COOH is 1.7 X 10^-5 and concentration of H⁺ ions is 3.4 X 10^-4.Then, find out initial concentration of CH₃COOH molecules.
1. 3.4 X 10^-4
2. 3.4 X 10^-3
3. 6.8 X 10^-4
4. 6.8 X 10^-3

4.

The formation of phosgene is represented as,
CO + Cl₂ $⇌$ COCl₂
The reaction is carried out in 500 mL flask. At equilibrium o.3 mole of phosgene, 0.1 mole of CO and 0.1 mole of Cl₂ are present. The equilibrium constant of the reaction is:
1. 30
2. 15
3. 5
4. 3

5.

The reaction quotient (Q) for the reaction, $N_{2} (g) + 3 H_{2} (g) \overset{}{⇌} 2 {NH}_{3} (g)$ is given by
$Q = \frac{{[{NH}_{3}]}^{2}}{[N_{2}] {[H_{2}]}^{3}}$ The reaction will proceed towards the right side, if
1. Q>K_c
2. Q=0
3. Q=K_c
4. Q<K_c

6.

The value of equilibrium constant of the reaction, $HI (g) \overset{}{⇌} \frac{1}{2} H_{2} (g) + \frac{1}{2} I_{2} (g) is 8.0 .$
The equilibrium constant of the reaction, $H_{2} (g) + I_{2} (g) \overset{}{⇌ 2 HI (g)}$ wiill be [2008]
1. $\frac{1}{16}$
2. $\frac{1}{64}$
3. 16
4. $\frac{1}{8}$

7.

Which salt undergoes hydrolysis?
1. CH₃COONa
2. KNO₃
3. NaCl
4. K₂SO₄

8.

The hydrolysis of the salt of a strong acid and a weak base is called:
1. Anionic hydrolysis
2. Cationic hydrolysis
3. Amphoteric hydrolysis
4. None of the above

9.

For the reaction, A+B $⇌ $3C at $25^{\circ}C$, a 3 litre vessel contains 1, 2, and 4 mole of A, B and C respectively. If K_c for the reaction is 10, then the reaction will proceed in:
1. forward direction
2. backward direction
3. in either direction
4. in equilibrium

10.

Which of the following is most soluble in water?
1. MnS (K_sp = 8x10^-37)
2. ZnS (K_sp = 7x10^-16)
3. Bi₂S₃ (K_sp = 1x10^-70)
4. Ag₂S (K_sp = 6x10^-51)

11.

The compound that does not act as Lewis acid is:
1. AlCl₃
2. BF₃
3. NH₃
4. FeCl₃

12.

The values of K_p1 and K_p2 for the reactions
$X ⇌ Y + Z . . . . . . . . (i)$
$and A ⇌ 2 B . . . . . . . . . (ii)$
are in ratio of 9:1, if degree of dissociation of X and A be equal, then total pressure at equilibrium (i) and (ii) are in the ratio
1. 3:1
2. 1:9
3. 36:1
4. 1:1

13.

For NH₄HS(s) $⇌$ NH₃ (g) + H₂S(g), the observed pressure for reaction mixture in equilibrium is 1.12 atm at 106 $°$ C. The value of K_p for the reaction is:
1. 3.136 atm²
2. 0.3136 atm²
3. 31.36 atm²
4. 6.98 atm²

14.

The relation for calculating pH of a solution containing weak acid and its salt is:
1. pH = pK_a + log $\frac{[Conjugate Base]}{[Acid]}$
2. pH = pK_a - log $\frac{[Conjugate Base]}{[Acid]}$
3. pH = pK_a + log $\frac{[Conjugate Base]}{[Salt]}$
4. pOH = pK_a - log $\frac{[Acid]}{[Conjugate Base]}$

15.

Solubility of a gas in liquid increases on:
1. Addition of a catalyst
2. Increasing the pressure
3. Decreasing the pressure
4. Increasing the temperature

16.

The molecule that is least likely to act as a Lewis base is:
1. CO
2. $F^{-}$
3. AlCl₃
4. PF₃

17.

The ionisation constant of ammonium hydroxide is 1.77 x 10^-5 at 298 K. Hydrolysis constant of ammonium chloride is
1. 5.65 x 10^-10
2. 6.50 x 10^-12
3. 5.65 x 10^-13
4. 5.65 x 10^-12

18.

For a given solution pH = 6.9 at 60 $°$ C, where K_w=10^-12. The solution is:
1. acidic
2. basic
3. neutral
4. unpredictable

19.

The stronger Bronsted based is:
1. ClO^-
2. Cl $O_{2}^{-}$
3. Cl $O_{3}^{-}$
4. Cl $O_{4}^{-}$

20.

The equilibrium, 2SO₂ (g) + O₂ (g) $⇌$ 2SO₃ (g)
shifts forward if:
1. a catalyst is used
2. an absorbent is used to remove SO₃ as soon as it is formed
3. small amounts of reactants are used
4. none of the above

21.

The pH of blood is maintained by CO₂ by and H₂CO₃ in the body and chemical constituents of blood. This phenomenon is called:
1. colloidal
2. buffer action
3. acidic
4. salt balance

22.

At temperature T, a compound AB₂ (g) dissociates according to the reaction 2AB₂ $⇌$ 2AB(g) +B₂(g) with a degree of dissociation x, which is small compared with unity. The expression for K_p, in terms of x and the total pressure P , is:
1. Px³/2
2. Px²/3
3. Px³/3
4. Px²/2

23.

For the reactions,
A $⇌$ B; K_c = 2
B $⇌$ C; K_c = 4
C $⇌$ D; K_c = 6
K_c for the reaction, A $⇌$ D is:
1. (2+4+6)
2. (2x4)/6
3. (4x6)/2
4. 2x4x6

24.

For the reaction equilibrium,
2NOBr(g) $⇌$ 2NO(g) + Br₂(g), if $P_{B r_{2}}$ = P/9 at equilibrium and P is total pressure. The ratio of K_p/P is equal to:
1. 1/9
2. 1/81
3. 1/27
4. 1/3

25.

Which of the following salts will give the highest pH in the water?
1. KCl
2. NaCl
3. Na₂CO₃
4. CuSO₄

26.

An aqueous solution of which salt has the lowest pH?
1. NaOH
2. NH₄Cl
3. Na₂CO₃
4. NaCl

27.

The following equilibria are given
N₂ + 3H₂ $⇌$ 2NH₃, K₁
N₂ + O₂ $⇌$ 2NO, K₂
H₂ + $\frac{1}{2}$ O₂ $⇌$ H₂O, K₃
The equilibrium constant of the reaction, 2NH₃ + $\frac{5}{2}$ O₂ $⇌$ 2NO + 3H₂O in terms of K₁, K₂and K₃is
1. $K_{1} K_{3}^{3} / K_{2}$
2. $K_{2} K_{3}^{3} / K_{1}$
3. K₁K₂K₃
4. K₁K₂/K₃

28.

At a certain temperature, 2HI $⇌$ H₂ +I₂ only 50% HI is dissociated at equilibrium. The equilibrium constant is:
1. 1.0
2. 3.0
3. 0.5
4. 0.25

29.

In the reaction, PCl₅$⇌ $PCl₃ + Cl₂, the amounts of PCl₅, PCl_3, and Cl₂ at equilibrium are 2 moles each and the total pressure is 3 atm. The equilibrium constant K_p is:
1. 1.0 atm
2. 2.0 atm
3. 3.0 atm
4. 6.0 atm

30.

On addition of inert gas at constant volume to the reaction, N₂ + 3H₂ $⇌$ 2NH₃ at equilibrium:
1. the reaction halts
2. forward reaction is favored
3. the reaction remains unaffected
4. backward reaction is favored

31.

In which of the following case reaction goes farthest to completion?
1. K=10³
2. K=10^-2
3. K=10
4. K=10⁰

32.

For the reversible reaction,
N₂ (g) + 3H₂(g) $⇌$ 2NH₃ (g) + heat
the equilibrium shifts in forward direction
1. by increasing the concentration of NH₃ (g)
2. by decreasing the pressure
3. by decreasing the concentrations of N₂ (g)and H₂(g)
4. by increasing pressure and decreassing temperature

33.

The strongest acid among the following is:
1. H₂SO₄
_2. HClO₃
3. HClO₄
4. H₂SO₃

34.

The conjugate acid of NH₂^- is
1. N₂H₄
2. N $H_{4}^{+}$
3. NH₄OH
4. NH₃

35.

The pH of a solution obtained by mixing 50ml of 0.4N HCl and 50ml of 0.2M NaOH is:
1. 13
2. 12
3. 1.0
4. 2.0

36.

In which of the following reaction the value of K_p will be equal to K_c ?
$1 . N_{2} (g) + O_{2} (g) ⇌ 2 NO (g)$
$2 . {PCl}_{5} (g) ⇌ {PCl}_{3} (g) + {Cl}_{2} (g)$
$3 . 2 {NH}_{3} (g) ⇌ N_{2} (g) + 3 H_{2} (g)$
$4 . 2 {SO}_{2} (g) + O_{2} (g) ⇌ 2 {SO}_{3} (g)$

37.

$\frac{K_{p}}{K_{c}}$ for the gaseous reaction:
$I . 2 A + 3 B ⇌ 2 C$
$II . 2 A ⇌ 4 B$
$III . A + B + 2 C ⇌ 4 D$
Would be respectively:
1. (RT)^-3, (RT)², (RT)⁰
2. (RT)^-3, (RT)-², (RT)^-1
3. (RT)^-3, (RT)², (RT)
4. None of the above

38.

The amount of CaC₂O₄ (molecular weight =128) will dissolve in distilled water to make 1 liter of a saturated solution is:
[K_sp (CaC₂O₄) = 2.5 x 10^-9]
1. 0.0064 g
2. 0.1280 g
3. 0.0128 g
4. 1.2800 g

39.

Ostwald dilution law for weak electrolyte HA can be given as
$(1) K_{a} = \frac{{Cα}^{2}}{(1 - α)}$
$(2) Ka = {Cα}^{2} if α \to 0$
$(3) K_{a} = \frac{{Cλ}^{2}}{λ^{2} (λ^{2} - λ)}$
$(4) All of the above$

40.

The molecule that is least likely to behave as Lewis base is:
1. NH₃
2. BF₃
3. OH^-
4. H₂O

41.

K_c and K_p are not equal for a reaction given below:
1. 2NO(g) $⇌$ N₂(g) + O₂(g)
2. SO₂(g) + NO₂(g) $⇌$ SO₃(g) + NO(g)
3. H₂(g) + I₂(g) $⇌$ 2HI(g)
4. 2C(s) + O₂(g) $⇌$ 2CO₂(g)

42.

Which one of the following molecular hydrides acts as a Lewis acid?
1. NH₃
2. H₂O
3. B₂H₆
4. CH₄

43.

If the concentration of OH^- ions in the reaction
Fe(OH)³ (s) $⇌$ Fe³⁺ (aq) + 3OH^-(aq) is decreased to 1/4 times, then equilibrium concentration of Fe³⁺ will increase by
(a) 8 times (b) 16 times
(c) 64 times (d) 4 times

44.

The pOH of a solution at 25 $°$ C that contains 1 x 10^-10 M of hydronium ions is:
1. 7.00
2. 4.00
3. 9.00
4. 1.00

45.

At a certain temperature the following equilibrium is established, CO(g) + N0₂(g) $\overset{}{⇌}$ CO₂(g)+ NO(g)One mole of each of the four gas is mixed in one litre container and the reaction is allowed to reach equilibrium state. When excess of baryta water (Ba(OH)₂) is added to the equilibrium mixture, the weight of white ppt (BaCO₃) obtained is 236.4 gm. The equilibrium constant K_c of the reaction is (Ba = 137)
(1) 1.2
(2) 2.25
(3) 2.1
(4) 3.6

Fill OMR Sheet*

*If above link doesn't work, please go to test link from where you got the pdf and fill OMR from there

CLICK HERE to get FREE ACCESS for 2 days of ANY NEETprep course

Please be patient as the PDF generation may take up to a minute.

Fill OMR Sheet*