Question

a sample of gas occupies a volume of 1025ml at 75C and 0.75atm. what will be the new volume if temperature decreases to 35C and pressure increases to 1.25atm?

Answer 1

544.34 mL

Step-by-step explanation:

• Combined gas law is a law that combines both Boyle's law and Charles's law.
• According to the combined gas law the volume of a fixed mas of a gas is directly proportional to absolute temperature but inversely proportional to pressure.

That is;
`(P1V1)/(T1) =(P2V2)/(T2)`

in our case we are given;

Initial volume, V1 = 1025 mL

Initial temperature, T1 = 75 °C (But K = °C + 273.5)

= 348.5 K

Initial pressure, P1 = 0.75 atm

New temperature, T2 = 308.15 K (35°C +273.15)

New pressure , P2 = 1.25 atm

We are required to calculate the new volume, V2

Replacing the known variables in the equation of combined gas law we can find the new volume;

`V2=(P1V1T2)/(P2T1)`

`=((1025mL)(0.75atm)(308.15K))/((1.25atm)(248.15K))`

`=544.34mL`

Therefore, the new volume is 544.34 mL