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Question
One mole of a gas expands by 3L against a constant pressure of 3 atmosphere. Calculate the work done in -
(a) L.atmosphere
(b) Joules
(c) Calories
Solution
Data: P = 3atm
ΔV = 3L
solution:
W = -PΔV
W = -3 x 3
W = -9L.atm
1L.atm = 101.3J
-9L.atm = -9 × 101.3J
W = -911.7J
4.184J = 1cal
∴ -911.7J = -911.7/4.184
W = -217.9cal
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