Question

At a certain temperature, a 24.5-L container holds four gases in equilibrium. Their masses are 3.5 g SO3 , 4.6 g SO2 , 13.4 g N2 , and 0.98 g N2O .

SO,, 13.4 g 52T At a certain temperature, a 24.5-L container holds four gases in equilibrium. Their masses are 3.5 g SO2,4 Ny, and 0.98 g N,O. What is the value of the equilibrium constant at this temperature for the reaction of SO2 with N20 to form SO3 and N2? Make sure you balance the reaction using the lowest whole-number coefficients. Kc = .334

Answer 1

Reaction between SO₂ and N₂O to form SO₃ and N₂ is as shown

SO2(g) + N20(9) + S03(9) + N2(9

This is the balanced chemical reaction.

Molar mass of SO₂=Molar mass of S+2xMolar mass of O=32 g/mol+2x16 g/mol=32 g/mol+32 g/mol=64 g/mol

Molar mass of N₂O=2xMolar mass of N+Molar mass of O=2x14 g/mol+16 g/mol=28 g/mol+16 g/mol=44 g/mol

Molar mass of SO₃=Molar mass of S+3xMolar mass of O=32 g/mol+3x16 g/mol=32 g/mol+48 g/mol=80 g/mol

Molar mass of N₂=2xMolar mass of N=2x14 g/mol=28 g/mol

Number of moles of SO₂=Given mass/Molar mass=4.6 g/64 g/mol=0.07 mol

Number of moles of N₂O=Given mass/Molar mass=0.98 g/44 g/mol=0.02 mol

Number of moles of SO₃=Given mass/Molar mass=3.5 g/80 g/mol=0.04 mol

Number of moles of N₂=Given mass/molar mass=13.4 g/28 g/mol=0.48 mol

We know that concentration=number of moles/volume of solution (L)

Also equilibrium constant Kc is the ratio of product of concentrations of products at equilibrium to product of concentrations of reactants at equilibrium raised to power their stoichiometric coefficients.

So Kc=[SO₃][N₂]/[SO₂][N₂O]

=(0.04 mol/24.5 L)(0.48 mol/24.5 L)/{(0.07 mol/24.5 L)(0.02 mol/24.5 L)}

=13.71

So the equilibrium constant Kc=13.71