Question

The pressure (P) after mixing is

(A) 5 atm
(B) 2.5 atm
(C) 2 atm
(D) 4 atm

Answer 1

Hint: To calculate the total pressure of the gas, Dalton law of partial pressure is applied. The pressure in the third chamber is the total pressure which is the sum of both the pressure pressure exerted by two chambers

Complete step by step answer:
Given,
${P_1}$ is 2atm
${P_2}$ is 3atm
${V_1}$ is 1 ltr
${V_2}$ is 2 ltr
${V_{Total}}$ is 2 ltr
The Dalton law of partial pressure states that the total pressure exerted by the gaseous mixture is equal to the sum total of the individual partial pressure exerted by the gases molecule.
Example: There are two gases molecule (gas A and gas B) present having individual value of partial pressure. The total pressure exerted by the mixture of gas A and gas B is equal to the sum of the individual partial pressure exerted by both gas A and B.
The pressure exerted by the individual gas molecule present in a mixture of gases is known as partial pressure.
Dalton's law formula is given as shown below.
${P_{total}} = {P_1} + {P_2} + {P_3}$ ${P_n}$
The formula to calculate the total partial pressure is shown below.
${P_{total}} = {P_1} + {P_2}$
${P_{total}} = 2 + 3$
$\Rightarrow {P_{total}} = 5$
Thus, the total pressure after mixing of two gases present in the chamber is 5 atm.

So, the correct answer is Option A.

Note: Dalton’s law of partial pressure helps in determining the pressure of dry gas only. Unless the individual gases present do not react chemically with each other they do not affect the pressure.