One litre of helium gas at a pressure 76 cm. of Hg and temperature 27oC is heated till its pressure and volume are double. The final ternperature attained by the gas is:

Initial volume of the gas V1 = 1 litre initial pressure of the gas P1 = 70 cm of HgFinal pressure of the gas P2 = 2×76 = 152 cm of HgFinal volume of the gas V2 = 2 litreAccording the Gay Lussac law we haveP1V1T1 = p2V2T2  or 76×1300 = 152×2T21300 = 4T2 or T2 = 4 × 300 = 1200 K = 9270C