For the reaction, \(2 \mathrm{NH}_3(s)+\mathrm{CO}_2(g) \rightleftharpoons \mathrm{NH}_2 \mathrm{CONH}_2(a…

For the reaction, \(2 \mathrm{NH}_3(s)+\mathrm{CO}_2(g) \rightleftharpoons \mathrm{NH}_2 \mathrm{CONH}_2(a q)+\mathrm{H}_2 \mathrm{O}(t)\), find the value of equilibrium constant at 295 K. Given, standard Gibbs energy change at the given temperature is \(13.9 \mathrm{kJmol}^{-1}\).
  1. \(2.88 \times 10^2\)
  2. \(2.58 \times 10^2\)
  3. \(2.40 \times 10^2\)
  4. \(2.65 \times 10^2\)

Solution

\(\begin{aligned} & \Delta G^{\circ}=-2.303 n R T \log K_C \\ & -13.9 \times 10^3 \mathrm{~J}=-2.303 \times 1 \times 8.314 \times 295 \log K_C \\ & \Rightarrow \quad \log K_C=\frac{-13.9 \times 10^3}{-2.303 \times 1 \times 8.314 \times 295}=2.46 \\ & \Rightarrow \quad K_C=10^{2.46} \Rightarrow 288.4=2.88 \times 10^2 \end{aligned}\) Hence, option (a) is correct.

Asked in: AP EAMCET 2020 (21 Sep Shift 2)

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