Question

The equilibrium constant, K, of a reaction at a particular temperature is determined by the concentrations or pressures of the reactants and products at equilibrium.

For a gaseous reaction with the general form

aA+bB⇌cC+dD

the Kc and Kp expressions are given by

Kc=[C]c[D]d[A]a[B]b

Kp=(PC)c(PD)d(PA)a(PB)b

The subscript c or p indicates whether K is expressed in terms of concentrations or pressures. Equilibrium-constant expressions do not include a term for any pure solids or liquids that may be involved since their composition does not change throughout the reaction. The standard state of a pure substance is the pure substance itself, and although the quantity may change the sample remain pure. The concentration is effectively equal to 1, and will not impact the magnitude of K.

The following reaction was performed in a sealed vessel at 747 ∘C :

H2(g)+I2(g)⇌2HI(g)

Initially, only H2 and I2 were present at concentrations of [H2]=3.75M and [I2]=2.65M . The equilibrium concentration of I2 is 0.0700 M . What is the equilibrium constant, Kc, for the reaction at this temperature?

Express your answer numerically.

Answer 1

Solution Reaction R H₂ (9) + Initial (I) 875 Concentration Iz (9) 265 HI o - Eherage (6) Concentration X +2x 2 % equilibrium € 3.75-x Concentration cotto here the reactants by x and H reaction Shift towards and Iz and decrease produced by increau 2x .. 265 – 1 = 0 ozo x = 2.58 So the equilibrium concentration of HI and the can be find [HI] - 2x2.58 - 5.16 m HJ 379-288- tot+M M T W T F S S

[ Products [ Readants] [Mg] [I ] (5.1692 [1] [- 0700) = 325