Question

For the equilibrium, $2NOCl\left(g\right)\rightleftharpoons 2NO\left(g\right)+C{l}_2\left(g\right)$ the value of the equilibrium constant, $K_{c}is3.75\times {10}^{–6}at1069K.$ Calculate the $K_p$ for the reaction at this temperature?

Answer 1

Given,
For the reaction $2NOCl\left(g\right)\rightleftharpoons 2NO\left(g\right)+C{l}_2\left(g\right);Kc=3.75\times {10}^{–6},T=1069K$ and
$R=0.0831$

Step 1: Formula

We know that,

$K_p=K_c(RT{)}^{△n}\dots ..(i)$

where $△n=$(number of moles of gaseous products) –(number of moles of gaseous reactants)
in the balanced chemical equation.

Step 2: Value of $△n$

So, for the above reaction,

$△n=(2+1)-2=1$

Step 3: Value of $K_p$

Putting values in equation $\left(i\right),$ we get,

$K_p=3.75\times {10}^{–6}(0.0831\times 1069)$

$K_p=0.033=3.3\times {10}^{-2}$

Final answer:

$K_p$ for the reaction is $3.3\times {10}^{-2}$