Question

Question #675cd

Answer 1

I assume the question refers to 4 L of gas, and asks for the new volume after the pressure and the temperature are doubled.

This can be solved by using the combined gas law,

`(P_1V_1)/T_1 = (P_2V_2)/T_2`.

You start with a pressure of `P_1` and end with a pressure of `P_2 = 2*P_1`. Likewise, the initial temperature is `T_1`, and the final temperature will be `T_2 = 2 * T_1`.

So, we can determine `V_2` from the combined gas law equation

`V_2 = P_1/P_2 * T_2/T_1 * V_1 => V_2 = P_1/(2*P_1) * (2 * T_1)/T_1 * V_1`

It's evident that `V_2 = V_1`, since both the pressure and the temperature terms cancel out.

This would have also been the case if the question said 4 moles of gas, since the combined gas law assumes that the number of moles is constant.

You would get the same result, `V_("final") = V_("initial")`.

SInce the question provides a value for `V_1`, the answer is

`V_2 = V_1 = 4` `"L"`.