Question

How much energy is absorbed by 10 kg molecule of an ideal gas, if it expands from an initial pressure of 8 atm to 4 atm at a constant temperature of $ 27{}^\circ C $ ?

• A. $ 1.728\times {{10}^{7}}J $
• B. $ 2.8\times {{10}^{6}}J $
• C. $ 5J $
• D. $ 10J $
• E. $ 15J $

Answer 1

Answer: (A)

Q = work done by the gas $ Q=\mu RT{{\log }_{e}}\left( \frac{{{p}_{1}}}{{{p}_{2}}} \right) $ $ Q=(10\times 1000\text{ }mol)\times (8.31) $ $ \times 300\times {{\log }_{e}}\left( \frac{8}{4} \right) $ $ Q={{10}^{4}}\times 8.31\times 300\times 2.302\times 0.301 $ $ Q=1.728\times {{10}^{7}}J $