Question

The data below refer to the following reaction: 2NO(g) + I2(g) 2NOI(g) Concentration (M) [NO] [I2] [NOI] Initial 2.0 4.0 1.0 Equilibrium 1.0 — — Find the concentration of I2 when the system reaches equilibrium.

Answer 1

3.5 mol·L⁻¹

Step-by-step explanation:

1. Set up an ICE table.

`\begin{array}{cccccc}\text{2NO} & + & \text{I}_(2) &\, \rightleftharpoons \, & \text{2NOI} & & \\ 2.0 & & 4.0 & & 1.0 & & \\ -2x & & -x & & +2x & & \\ 2.0-2x & & 4.0-x & & 1.0+2x & & \\\end{array}`

2. Solve for x

The equilibrium concentration of NO is 1.0 mol·L⁻¹, so

1.0 = 2.0 - 2x

2x + 1.0 = 2.0

2x = 1.0

x = 0.5

3. Calculate the equilibrium concentration of I₂

[I₂] = 4.0 - x = 4.0 - 0.5 = 3.5 mol·L⁻¹