Question

When heated, the compound decomposes as follows:

$N{H}_{4}COON{H}_2\left(s\right)\rightleftharpoons 2N{H}_3\left(g\right)+C{O}_2\left(g\right)$

at a certain temperature, the equilibrium pressure of the system is 0.318 atm. $K_p$ for the reaction is?

• A. 0.128
• B. 0.0225
• C. $4.76\times {10}^{-3}$
• D. None of the above

Answer 1

The correct option is C $4.76\times {10}^{-3}$

${NH}_4{CO}_2{NH}_2\left(s\right)\rightleftharpoons {2NH}_3\left(g\right)+{CO}_2\left(g\right)$

Let,

total moles of gases $=2+1=3$

mole fraction of ${NH}_3=2/3$

mole fraction of ${CO}_2=1/3$

For given reaction,

$K_P=\left(P_{{NH}_3}^2\right)\times \left(P_{{CO}_2^2}\right)={[0.318\times \frac{2}{3}]}^2[0.318\times 1/3]$

$\Rightarrow K_P=4.76\times {10}^{-3}$

$\therefore$ the value of $K_P$ for this reaction is $4.76\times {10}^{-3}$.