A 7.50 × 10^-³m³ bottle contains 0.0200 kg of oxygen gas,O₂,at 77.0 °C.What is the pressure exerted on the inner walls of the flask by the oxygen gas? Note: the atomic mass of O is 15.9994 u.

Question

Quizplus · Accepted Answer

Using the ideal gas law:
PV = nRT
where P is the pressure, V is the volume, n is the number of moles of gas, R is the gas constant, and T is the temperature in Kelvin.

We first need to find the number of moles of oxygen gas present:

n = m/M
where m is the mass of the oxygen gas and M is the molar mass of oxygen gas.

M = 2(15.9994 u) = 31.9988 g/mol

Converting the mass of oxygen gas to kg:

m = 0.0200 kg

n = 0.0200 kg/31.9988 g/mol = 0.000625 mol

Next, we need to convert the volume to m³:

V = 7.50 × 10¹¹ P0³m³ = 7.50 × 10¹⁷ nm³

V = 7.50 × 10¹⁷ nm³ × (1 m³/10⁰⁹ nm³) = 7.50 m³

Finally, we can solve for the pressure:

P = nRT/V

R = 8.314 J/mol·K
T = 77.0 °C = 350.15 K

P = (0.000625 mol)(8.314 J/mol·K)(350.15 K)/(7.50 m³)
P = 2.43 × 10⁵ Pa

Therefore, the answer is choice C.

A 750 × 10-³m³ Bottle Contains 0

A 750 × 10^-³m³ Bottle Contains 0