Question

A mixture of gases was found to have a total pressure of 950mmHg. Gas number one has a pressure of 335mmHg. Gas number two has a pressure of 456mmHg. What is the pressure exerted by gas number three?

Answer 1

Answer: The partial pressure of gas number 3 is 159 mmHg

Explanation:

Dalton's law of partial pressure states that the total pressure of the system is equal to the sum of partial pressure of each component present in it.

To calculate the partial pressure of gas number 3, we use the law given by Dalton, which is:

$P_T=p_{1}+p_{2}+p_3$

We are given:

Total pressure of the tank, $P_T$ = 950 mmHg

Vapor pressure of gas number 1, $p_{1}$ = 335 mmHg

Vapor pressure of gas number 2, $p_{2}$ = 456 mmHg

Putting values in above equation, we get:

$950=335+456+p_3\\\\p_{3}=[950-(335+456)]=159mmHg$

Hence, the partial pressure of gas number 3 is 159 mmHg