Question

2 SO2(g) + O2(g) 2 SO3(g) Assume that Kc = 0.0680 for the gas phase reaction above. Calculate the corresponding value of Kp for this reaction at 84.5°C.

Answer 1

Answer: The corresponding value of $K_p$ for this reaction at 84.5°C is 0.00232

Explanation:

$2SO_2(g)+O_2(g)\rightarrow 2SO_3(g)$

Relation of with is given by the formula:

$K_p=K_c(RT)^{\Delta ng}$

where,

= equilibrium constant in terms of partial pressure = ?

$K_c$ = equilibrium constant in terms of concentration = 0.0680

R = Gas constant = $0.0821\text{ L atm }mol^{-1}K^{-1}$

T = temperature  =$84.5^0C=(273+84.5)K=357.5K$

$\Delta n_g$ = change in number of moles of gas particles = $n_{products}-n_{reactants}=2-3=-1$

Putting values in above equation, we get:

$K_p=0.0680\times (0.0821\times 357.5)^{-1}\\\\K_p=0.00232$

Thus the corresponding value of $K_p$ for this reaction at 84.5°C is 0.00232