Answer to Question #256821 in Chemistry for MCC

Question

Given the following amounts of gases calculate the number of moles of each gas. Calculate the volume each amount of gas would occupy at 100°C and 15 atm.

a. 5.8g NH₃

b. 48g O₂

Answer 1

Solution:

The molar mass of NH₃ is 17.03 g/mol

The molar mass of O₂ is 32.00 g/mol

Calculate the moles of each gas:

a) (5.8 g NH₃) × (1 mol NH₃ / 17.03 g NH₃) = 0.34 mol NH₃

Moles of NH₃ = 0.34 mol

b) (48 g O₂) × (1 mol O₂ / 32.00 g O₂) = 1.50 mol O₂

Moles of O₂ = 1.50 mol

The Ideal Gas equation can be used: PV = nRT

To find the volume each amount of gas, solve the equation for V:

V = nRT / P

R = 0.0821 L atm mol^-1 K^-1

T = 100°C = 373.15 K

a) V(NH₃) = (0.34 mol × 0.0821 L atm mol^-1 K^-1 × 373.15 K) / (15 atm) = 0.6944 L = 0.69 L

Volume of NH₃ = 0.69 L

b) V(O₂) = (1.50 mol × 0.0821 L atm mol^-1 K^-1 × 373.15 K) / (15 atm) = 3.0636 L = 3.06 L

Volume of O₂ = 3.06 L

Answers:

a) 0.34 mol NH₃; 0.69 L NH₃

b) 1.50 mol O₂; 3.06 L O₂