Gases are measured using three variables: temperature (T), pressure (P), and volume (V).
When more than one variable is changing you use the universal gas law which combines Boyle's Law and Charles's Law into one general equation.
That equation is:
(P1 x V1)/T1 = (P2 x V2)/T2
where P1, V1 & T1 are initial conditions and P2,V2,T2 are final conditions.
There are three important things you need to watch when solving these problems:
1: make sure the temperature is converted to degrees Kelvin using the formula: K = 273.15 + degrees C
2. make sure the units for pressure are the same for the initial state and final state. You do not have to change them to kPa unless that is the units you are asked to use in the final answer.
3. make sure the units for volume are the same for the initial and final states.
Once you have done this, put your known values into the equation above and solv e for the unknown.
In this problem:
P1 = 1.5 atm
V1 = 1 liter
T1 = 25 degrees C = 298.15 K
P2 = 6 atm
V2 = ?
T2 = 100 degrees C = 373.15 K
(1.5 x 1)/298.15 = (6V2)/373.15
first multiply both sides by 373.15 and you get
(373.15 x 1.5 x1)/298.15 = 6V2
now divide both sides by 6 to find V2
(373.15 x 1.5 x1)/(298.15 x 6) = V2
solving you get V2 = .313 liters or 313 mL
Notice that in this case the increased pressure had a greater effect on the final volume than the increased temperature.