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debb1232003
Nov 28, 2010, 03:19 PM
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

Unknown008
Nov 29, 2010, 01:47 AM
Use the ideal gas equation.

PV = nRT

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:

\frac{PV}{T} = k

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:

\frac{P_1V_1}{T_1} = \frac{P_2V_2}{T_2}

You only need to convert the temperature to Kelvin.