Question

A student collected a 40.0 mL sample of H_{2} 2 ​ gas at a temperature of 20.0°C and pressure of 720.0 mmHg. The next day the temperature was still 20.0°C but the sample's volume has decreased to 38.4 mL. What is the new pressure, in mm Hg?

Answer 1

Answer: 750 mmHg

Explanation:

To calculate the new pressure, we use the equation given by Boyle's law. This law states that pressure is inversely proportional to the volume of the gas at constant temperature.

The equation given by this law is:

$P_1V_1=P_2V_2$

where,

$P_1$ = initial pressure of gas= 720.0 mmHg

$V_1$ =  initial volume of gas = 40.0 ml

$P_2$ = final pressure of gas= ?

$V_2$ = final volume of gas = 38.4 ml

Putting values in above equation, we get:

$720.0\times 40.0=P_2\times 38.4$

$P_2=750mmHg$

Thus the new pressure will be 750 mmHg