Physical Chemistry MCQ with Answers

Physical Chemistry MCQ with Answers

216) The equilibrium constant K_p for a homogeneous gaseous reaction is 10⁻⁸. The standard Gibb′s free energy change, ΔG^o for the reaction is:

Answer is:

10.059 kcal

Explanation:

ΔG^o = −2.303RT log K

217) If pH of a saturated solution of Ba(OH)₂ is 12, the value of K_sp is:

Answer is:

5 x 10⁻⁷ M³

Explanation:

K_sp = [Ba²⁺][OH⁻]²

218) What amount of Cl₂ gas liberated at anode, if 1 A current is passed for 3 min from NaCl solution?

Answer is:

0.66 gm

219) 100 mL HCN of 0.1M is titrated with 100 mL 0.1M NaOH solution. At the neutral point, pH of this solution will be: (pK_a of HCN = 4.74)

Answer is:

8.72

Explanation:

pH = (1⁄2) x (pK_w + pK_a + pK_b)

220) The pH of blood is 7.4. If the buffer in blood is CO₂ and HCO₃⁻, then the ratio of conjugate base to acid (H₂CO₃) to maintain the pH of the blood will be:

Answer is:

11.25

Explanation:

[H⁺] = 10^−pH

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