Suppose a 24.3 mL sample of helium gas at 25 degrees celsius and 1.01 atm is heated to 50 degree celsius and compressed to a volume of 15.2 mL. What will be the pressure of the sample

Use the ideal gas equation.



Now, you can do a 'shortcut' since there are two constants here, namely the number of moles n and the ideal gas constant R.

This becomes:



And since the second case has the same constant, that is the same number of moles and the same ideal gas constant, you can have:



You only need to convert the temperature to Kelvin.