Question

A gas at 89 degrees C occupies 125.7mL at 123.3kPa. What volume does it occupy at 25 degrees C and 100.9kPa?

Answer 1

we can use the combined gas law equation

this shows the relationship between pressure, volume and temperature for a fixed mass of gas.

`(P1V1)/(T1) = (P2V2)/(T2)`

P1 is pressure, V1 is volume and T1 is temperature in Kelvin for the first instance

P2 is pressure, V2 is volume and T2 is temperature for the second instance.

Temperature is given in °C we have to convert it to Kelvin

T1 is - 89 °C + 273 = 362 K

T2 is - 25 °C + 273 = 298 K

substituting the given values in the equation

`(123.3 kPa * 125.7 mL)/(362 K) = (100.9 kPa *V2 )/(298 K)`

V2 = 126.4 mL

the final volume is 126.4 mL