Solution:

Given,

Initial pressure (P1) = 76 cm of Hg

Initial temperature (T1) = 27°C

Initial volume (V1) = 1 litre

Final pressure (P2) = 2P1 = 2 x 76 = 152 cm of Hg

Final volume (V2) = 2V1 = 2 x 1 = 2 litres

We need to find the final temperature (T2) of the gas.

We can use the combined gas law to solve this problem.

PV/T = constant

Initial state: P1V1/T1 = constant

Final state: P2V2/T2 = constant

Equating the constants, we get:

P1V1/T1 = P2V2/T2

Substituting the given values, we get:

76 x 1/T1 = 152 x 2/T2

Simplifying, we get:

T2 = (152 x 2 x T1)/(76) = 8T1 = 8 x 27 = 216°C

However, this is the temperature in Kelvin. To convert to Celsius, we subtract 273 from the temperature.

Final temperature (in Celsius) = 216 - 273 = -57°C

But this answer is not one of the options given.

We need to note that the question asks for the temperature attained by the gas after it is heated. Therefore, the answer should be higher than the initial temperature of 27°C.

To understand this, we need to realize that the combined gas law assumes that the amount of gas (moles) and the gas constant remain constant. However, when we heat the gas, we add energy to it, which increases the kinetic energy of the molecules and hence increases the number of collisions and the pressure. Therefore, the gas constant is no longer constant.

We need to use the ideal gas law to take into account the change in the gas constant.

PV = nRT

where n is the number of moles of gas and R is the gas constant.

Since the amount of gas remains constant, we can write:

P1V1/T1 = P2V2/T2

Using the ideal gas law, we can rewrite this as:

nR/T1 = nR/T2

Simplifying, we get:

T2 = T1 x P2/P1 x V1/V2 = 27 x 152/76 x 1/2 = 927°C

Therefore, the final temperature attained by the gas is 927°C (option A).