Question

A sample of nitrogen gas has a volume of 478 cm3 and a pressure of 104.1 kPa. What volume would the gas occupy at 88.2 kPa if the temperature remains constant?

Answer 1

1.    To solve this we assume that the gas is an ideal gas. Then, we can use the ideal gas equation which is expressed as PV = nRT. At a constant temperature and number of moles of the gas the product of PV is equal to some constant. At another set of condition of temperature, the constant is still the same. Calculations are as follows:

P1V1 =P2V2

V2 = P1 x V1 / P2

 V2 = 104.1 x 478 / 88.2

 V2 =564.17 cm^3

Answer 2

Answer:

$564 cm^3$

Explanation:

First we propose the ideal gas equation for each situation

$P.V=n.R.T$

Situation 1

$P_1.V_1= n. r.T$

$P_1= 104.1 KPa \\V_1= 478 cm^3$

Situation 2

$P_2.V_2= n. r.T\\P_2= 82.2 KPa \\V_2= ?$

R is a constant, the moles remain constant and also the temperature

Therefore we can say that

$P_1.V_1= P_2.V_2$

We cleared the volume in situation number two

$P_1.V_1= P_2.V_2\\V_2= \frac{P_1.V_1}{P_2}$

$V_2= \frac{104.1 KPa. 478cm^3}{88.2 KPa}\\V_2= 564 cm^3$