Calculate the equilibrium concentration of [N2][N2] if the initial concentrations are 2.25 MM N2N2 and 0.55 MM O2O2. (This N2/O2N2/O2 concentration ratio is the ratio found in air.)

The equilibrium concentration of N2 is 2.22765 M

Explanation:

The air pollutant NO is produced in automobile engines from the high-temperature reaction:

N2(g)+O2(g) <--> 2NO(g)  Kc=1.7 * 10^-3

Part A: Calculate the equilibrium concentration of N2 if the initial concentrations are 2.25 M N2 and 0.55 M O2. (This N2/O2 concentration ratio is the ratio found in air.)

Step 1: Data given

Initial concentration of N2 = 2.25 M

Initial concentration of O2 = 0.55M

Kc = 1.7 * 10^-3

Step 2: The initial concentrations

[N2] = 2.25 M

[O2] = 0.55 M

[NO] = 0M

Step 3: The concentrations at equilibrium

[N2] = 2.25 - x M

[O2] = 0.55 - x M

[NO] = 2x M

Step 4: Kc

Kc = 1.7 *10^-3 = (2x)² / (2.25 -x)(0.55 -x )

1.7 * 10^-3 = 4x² / (1.2375 - 2.80x  +x² )

0.0017x² - 0.00476x + 0.002104 = 4x²

3.9983x² + 0.00476x - 0.002104 = 0

x = 0.02235

[N2] = 2.25 - x M = 2.25 - 0.02235 = 2.22765 M

[O2] = 0.55 - x M = 0.55 - 0.02235 = 0.52765 M

[NO] = 2x M = 2* 0.02235 = 0.0447 M

The equilibrium concentration of N2 is 2.22765 M