Question

A sample of 88.0 g CO2 is held at 291 K in a 40.0 L container. What is the pressure this gas exerts on the container. Express your answer in kPa.

Answer 1

Answer:- 121 kPa.

Solution:- mass, temperature and volume are given for carbon dioxide gas asked to calculate the pressure this gas exerts on the container.

It is based on ideal gas law equation, PV = nRT .

Where, P is the pressure in atm, V is the volume in Liters, n is the number of moles of the gas, R is the universal gas constant and it's value is $\frac{0.0821atm.L}{mol.K}$ and T is the kelvin temperature.

Given data:- mass = 88.0 g

T = 291 K

V = 40.0 L

P = ?

We need to convert the mass to moles and for this we divide the mass by molar mass. Molar mass of carbon dioxide gas is 44.01 gram per mol.

$n=88.0g(\frac{1mol}{44.01g})$

n = 2.00 mol

The equation could be rearranged for pressure as:

$P=\frac{nRT}{V}$

Let's plug in the values and solve this for P.

$P=\frac{2.00mol*(\frac{0.0821atm.L}{mol.K})*291K}{40.0L}$

P = 1.1946 atm

Since the answer is asked to report in kPa, let's convert atm to kPa.

1 atm = 101.325 kPa

So, $1.1946atm(\frac{101.325kPa}{1atm})$

= 121 kPa

So, the pressure this gas exerts on the container is 121 kPa.