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

By applying Boyle's Law to the given conditions, the new pressure of the gas after its volume decreased from 40.0 mL to 38.4 mL while temperature remained constant is found to be 750.0 mmHg.

Step-by-step explanation:

The student has presented a situation where the volume of a gas sample decreased from 40.0 mL to 38.4 mL while the temperature remained constant at 20.0°C. To find the new pressure, we can use Boyle's Law, which states that the pressure of a gas is inversely proportional to its volume when temperature is held constant (P1V1 = P2V2).

The initial conditions are a volume (V1) of 40.0 mL and a pressure (P1) of 720.0 mmHg. The final volume (V2) is 38.4 mL. We want to find the new pressure (P2).

Plugging in the values, we get:

720.0 mmHg × 40.0 mL = P2 × 38.4 mL.

Solving for P2, we find:

P2 = (720.0 mmHg × 40.0 mL) / 38.4 mL.

P2 = 750.0 mmHg.

The new pressure of the H2 gas at 20.0°C and a volume of 38.4 mL is 750.0 mmHg.

Answer 2

Answer: 750 mmHg

Step-by-step 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* 40.0=P_2* 38.4`

`P_2=750mmHg`

Thus the new pressure will be 750 mmHg