Consider the following gaseous equilibria with equilibrium constants K₁ and K₂ respectively.

$$\begin{gathered} {\mathrm{SO}}_2\left(\mathrm{g}\right) + \frac{1}{2}{\mathrm{O}}_2\left(\mathrm{g}\right) \rightleftharpoons {\mathrm{SO}}_3\left(\mathrm{g}\right) \\ 2{\mathrm{SO}}_3\left(\mathrm{g}\right) \rightleftharpoons 2{\mathrm{SO}}_2 \left(\mathrm{g}\right) + {\mathrm{O}}_2\left(\mathrm{g}\right) \\ \mathrm{The} \mathrm{equilibrium} \mathrm{constants} \mathrm{are} \mathrm{related} \mathrm{as} \end{gathered}$$

• ${\mathrm{K}}_1^2 = \frac{1}{{\mathrm{K}}_2}$

• $2{\mathrm{K}}_1= {\mathrm{K}}_2^2$

• ${\mathrm{K}}_2=\frac{2}{{\mathrm{K}}_1^2}$

• ${\mathrm{K}}_2^2=\frac{1}{{\mathrm{K}}_1}$

In the reversible reaction,

A(s) + B(g) $\rightleftharpoons$C (g) + D(g) ΔG^° = -350kJ

Which one of the following statements is true?

• The entropy change is negative

• Equilibrium constant is greater than one

• The reaction should be instantaneous

• The reaction is thermodynamically not feasible

Consider the folowing equilibria with equilibrium constants K₁ and K₂ respectively,

SO₂  (g) + $\frac{1}{2}{\mathrm{O}}_2 \left(\mathrm{g}\right) \rightleftharpoons$SO₃ (g)

2SO₃ (g) $\rightleftharpoons$ 2SO₂ (g) + O₂ (g)

The equilibrium constants are related as

• 2K₁ = K${}_2^2$

• ${\mathrm{K}}_1^2 = \frac{1}{{\mathrm{K}}_2}$

• ${\mathrm{K}}_2^2 = \frac{1}{{\mathrm{K}}_1}$

• ${\mathrm{K}}_2 = \frac{2}{{\mathrm{K}}_1^2}$

0.023 g of sodium metal is reacted with 100cm³ of water. The pH of the result solution is

• 10

• 11

• 9

• 12

A buffer solution contains 0.1 mole of sodium acetate in 1000 cm³ of 0.1 M acetic acid. To the above buffer solution, 0.1 mole of sodium acetate is further added and dissolved. The pH of the resulting buffer is equal to

• pK_a - log2

• pK_a

• pK_a +2

• pK_a + log 2

The activation energy of  a reaction at a given temperature is found to be 2.303 RT J mol^-1. The ratio of rate constant to the Arrhenius factor is

• 0.01

• 0.1

• 0.02

• 0.001

pH value of which one of the following is not equal to one?

• 0.1 M CH₃COOH

• 0.1 M HNO₃

• 0.05 M H₂SO₄

• 50 cm³ 0.4 M HCl + 50 cm³ 0.2 M NaOH

A buffersolution contains 0.1 mole of sodium acetate dissolved in 1000 cm³ of 0.1 M acetic acid. To the above buffersolution, 0.1 mole of sodium acetate is further added and dissolved. The pH of the resulting buffer is 

• pK_a

• pK_a + 2

• pK_a - log 

• pK_a + log 2

H₂S is passed into one nm³ of a solution containing 0.1 mole of Zn²⁺ and 0.01 mole of Cu²⁺ till the sulphide ion concentration reaches to 8.1 × 10^-19 moles. Which one of the following statements is true?

[K_sp of ZnS and CuS are 3 × 10^-22 and 8 × 10^-36 respectively.]

• Only ZnS precipitates

• Both CuS and ZnS precipitate

• Only CuS precipitates

• No precipitation occurs

0.023 g of sodium metal is reacted with 100 cm³ of water. The pH of the resulting solution is

• 10

• 8

• 9

• 12