Which of the following statement is correct for vapor pressure?

• (A) Vapor pressure decreases with increase in temperature
• (B) Vapor pressure is independent of temperature
• (C) Vapor pressure increases with increase in temperature
• (D) Vapor pressure becomes zero at high temperature

Find the number of atoms present in 11.2 L of nitrogen gas at STP.

• (A) \( 3.01 \times 10^{23} \)
• (B) \( 6.02 \times 10^{23} \)
• (C) \( 12.04 \times 10^{23} \)
• (D) \( 1.204 \times 10^{23} \)

Which of the following is true for entropy?

• (A) Entropy decreases with increase in randomness
• (B) Entropy is the measure of randomness of a system
• (C) Entropy remains constant in every process
• (D) Entropy is always zero for gases

Calculate the solubility in \( mol dm^{-3} \) of sparingly soluble salt BaBr if its solubility product is \( 4.9 \times 10^{-13} \) at the same temperature.

• (A) \( 7 \times 10^{-7} \)
• (B) \( 7.5 \times 10^{-7} \)
• (C) \( 8 \times 10^{-7} \)
• (D) \( 4.9 \times 10^{-7} \)

Calculate the pH of 0.01 M strong dibasic acid.

• (A) 5.5
• (B) 2.5
• (C) 2.0
• (D) 1.7

The solubility product of \( PbCl_2 \) at 298 K is \( 3.2 \times 10^{-5} \). What is its solubility in \( mol dm^{-3} \)?

• (A) \( 8 \times 10^{-6} \)
• (B) \( 2 \times 10^{-2} \)
• (C) \( 5.6 \times 10^{-3} \)
• (D) \( 5 \times 10^{-2} \)

Identify \( Base_2 \) for the following equation according to Brønsted-Lowry theory: \( HCl(aq) + H_2O(l) \rightleftharpoons H_3O^+(aq) + Cl^-(aq) \)

• (A) \( H_3O^+(aq) \)
• (B) \( H_2O(l) \)
• (C) \( Cl^-(aq) \)
• (D) \( HCl(aq) \)

What is the pH of \( 2 \times 10^{-3} M \) solution of a monacidic weak base if it ionises to the extent of 5%?

• (A) 14
• (B) 10
• (C) 4
• (D) 2

A certain mass of a gas occupies a volume of 2.5 \( dm^3 \) at NTP. Calculate the change in volume of gas at the same temperature if pressure of gas is changed to 1.25 atm.

• (A) 3.0 \( dm^3 \)
• (B) 0.5 \( dm^3 \)
• (C) 4.5 \( dm^3 \)
• (D) 1.5 \( dm^3 \)

Identify conjugate acid and conjugate base for \( HCO_3^- \) ion respectively:

• (A) \( CO_3^{2-}  and  H_2CO_3 \)
• (B) \( H_2CO_3  and  CO_2 \)
• (C) \( CO_2  and  H_2CO_3 \)
• (D) \( H_2CO_3  and  CO_3^{2-} \)