From the information given, the hydrogen gas was cooled from a temperature of 150 °C to 50 °C. The final volume of the gas after being cooled came to 75ml.
To find out its original volume, we need to apply Charles law which is expressed as : V1 /T1 = V2 /T2
Where V1 is original volume
Where T1 is original temperature
Where V2 is the final volume
Where T2 is the final temperature.
We need V1 so V1 = (V2 × T1) ÷ T2
V1 = (75 × 150) ÷ 50
V1 = 225 ml
Original volume of the gas was 225 ml
