Answer:
819.45 K
Step-by-step explanation:
Use the Ideal Gas Law to make sense of this problem, PV = nRT. From this equation, we know that pressure is directly proportional to temperature and that volume is also directly proportional to temperature. Therefore, doubling the temperature would double the pressure, and doubling the temperature would also double the volume. In the described scenario, the temperature is doubled twice, so the temperature is quadrupled (i.e. three times its original amount has been added).
The initial temperature was 273.15 K. Multiply this by 3 to get your answer of 819.45 K.