What is the temperature of 0.59 mol of gas at a pressure of 1.5 atm and a volume of 12.9 L ?
399.68 K or just over 126 celcius.
Assuming it behaves as an ideal gas, you can say
Note that pressure and volume can be expressed in a number of different units, so you need to ensure that you use the gas constant in a form that is consistent with the other units that you're working with. As we're working in atmospheres as a pressure unit and litres as the unit of volume you need the gas constant in units of
Now rearrange for T you have