Chapter 15, Problem 15.70QP

Interpretation Introduction

Interpretation:

The equilibrium pressures of all the species has to be calculated using the given data.

Concept Introduction:

• Equilibrium constant: at equilibrium the ratio of products to reactants (each raised to the power corresponding to its stoichiometric coefficient) has a constant value, K

  For a general reaction, $\text{aA+bB}\rightleftarrows \text{cC+dD}$

  $\text{Equilibrium}\text{constant}\text{K}\text{=}\frac{{\left[\text{C}\right]}^{\text{c}}{\left[\text{D}\right]}^{\text{d}}}{{\left[\text{A}\right]}^{\text{a}}{\left[\text{B}\right]}^{\text{b}}}$

• Equilibrium constant can be expressed as the ratio of forward constant to the rate of backward rate constant for the reverse reaction.

    ${\text{K}}_{\text{c}}\text{=}\frac{{\text{k}}_{\text{f}}}{{\text{k}}_{\text{r}}}$

• Equilibrium constant at constant pressure:$K_p$

It is used to express the relationship between product pressures and reactant pressures.

  For a general reaction, $\text{aA+bB}\rightleftarrows \text{cC+dD}$

$\text{Equilibrium}\text{constant}{\text{K}}_p\text{=}\frac{P_C{}^{\text{c}}{P}_D{}^{\text{d}}}{P_A{}^{\text{a}}{P}_B{}^{\text{b}}}$

• $\begin{array}{l}{\text{K}}_{\text{p}}\text{=}{\text{K}}_{\text{c}}{\left(\text{RT}\right)}^{\text{Δn}}\\ \text{Δn}\text{-}\text{change}\text{in}\text{number}\text{of}\text{moles}\\ \text{R}\text{-}\text{Gas}\text{constant}\\ \text{T-Temperature}\end{array}$