Which one of the following statements is correct with respect to basic character ?

• PH₃ > P(CH₃)₃

• PH₃ = NH₃

• PH₃ > NH₃

• P(CH₃)₃ > PH₃

522.

75 mL of 0.2 M HCl is mixed with 25 mL of 1M HCl. To this solution, 300 mL of distilled water is added. What is the pH of the resultant solution?

• 1

• 2

• 4

• 0.2

If the ionic product of water (K_w) is 1.96 x 10^-14 at 35°C, what is its value at 10°C?

• 1.96 × 10^-14

• 3.92 × 10^-14

• 2.95  × 10^-14

• 1.96 × 10^-13

Which one of the following statements is correct?

• Bronsted-Lowery theory could not explain the acidic nature of BCl₃

• The pH of 0.01 M NaOH solution is 2.

• The ionic product of water at 25°C is 10^-10 mol²L^-2. 

• The pH of a solution can be calculated using the equation pH = log[H⁺].

One mole of A(g) is heated to 200°C in a one litre closed flask, till the following equilibrium is reached.

A(g) B(g)

The rate of forward reaction at equilibrium is 0.02 mol L^-1min^-1. What is the rate (in mol L-1min^-1) of the backward reaction at equilibrium?

• 0.04

• 0.01

• 0.02

• 1

Iron sulphide is heated in air to form A an oxide of sulphur. A is dissolved in water to give an acid. The basicity of this acid is

• 2

• 3

• 1

• zero

In which of the following reactions, the concentration of product is higher than the concentration of reactant at equilibrium? (K = equilibrium constant)

• A $\rightleftharpoons$ B; K = 0.001

• M  K = 10

• X $\rightleftharpoons$ Y; K = 0.005

• R $\rightleftharpoons$ P; K = 0.01

Study the following table:

Buffer solution	Volume (in mL) of 0 M weak acid	Volume (in mL) of 0.1 M sodium salt of weak acid
I	4.0	4.0
II	4.0	40.0
III	40.0	4.0
IV	0.1	10.0

Which of the two sets of butter solutions have least pH?

• I and II

• I and III

• II and III

• II and IV

Assertion (A): The pH of a buffer solution containing equal moles of acetic acid and sodium acetate is 4.8 (pK_a of acetic acid is 4.8).

Reason (R): The ionic product of water at 25°C is 10^-14mol².L^-2. The correct answer is

• Both (A) and (R) are true and (R) is the correct explanation of (A)

• Both (A) and (R) are true and (R) is not the correct explanation of (A)

• (A) is true but (R) is not true

• (A) is not true but (R) is true

At 550 K, the K_c for the following reaction is 10⁴ mol^-1L $\mathrm{X}\left(\mathrm{g}\right) + \mathrm{Y} \left(\mathrm{g}\right) \rightleftharpoons \mathrm{Z}\left(\mathrm{g}\right)$. At equilibrium, it was observed that $\left[\mathrm{X}\right] =\frac{1}{2}\left[\mathrm{Y}\right] =\frac{1}{2}\left[\mathrm{Z}\right]$. What is the value of [Z] (in mol L^-1) at equilibrium?

• 2 × 10^-4

• 10^-4

• 2 × 10⁴

• 10⁴