Step 1: Note what stays the same.
The gas is the same fixed amount and the pressure does not change. When pressure is held steady, we can use Charles's law, which links volume and temperature for a gas.
Step 2: Write Charles's law.
Charles's law says the volume of a gas is proportional to its absolute temperature. So $\dfrac{V_1}{T_1} = \dfrac{V_2}{T_2}$. Here $T$ must be in kelvin, not celsius.
Step 3: Change the temperatures to kelvin.
To go from celsius to kelvin we add $273$. So the start temperature is $T_1 = 27 + 273 = 300$ K and the final temperature is $T_2 = 327 + 273 = 600$ K.
Step 4: Put the numbers in.
Using the law, $\dfrac{V}{300} = \dfrac{V_2}{600}$.
Step 5: Solve for the final volume.
Cross multiply to get $V_2 = V \times \dfrac{600}{300}$. \[ V_2 = V \times 2 \]
Step 6: State the answer.
The temperature in kelvin doubled, so the volume also doubles. The final volume is twice the starting volume. \[ \boxed{2V} \]