A mole of X reacts at a constant pressure of 43.0 atm via the reaction
2 answers:
Answer:
Total energy change, ΔE = 61.929 kJ
Explanation:
Relationship between ΔH, ΔE and work done is given by first law of thermodynamics.
ΔE = ΔH - PΔV
Where,
ΔH = Change in enthalpy
ΔE = Change in internal energy
PΔV = Work done
Given,
ΔH = -75.0 kJ = -75000 J
P = 43.0 atm
ΔV = Final volume - initial volume
= (2.00 - 5.00) = -3.00 L
PΔV = 43 × (-3.00) = -129 L atm
1 L atm = 101.325 J
-129 L atm = 129 × 101.325 = -13071 J
ΔE = ΔH - PΔV
= -75000 - (-13071)
= -75000 + 13071
= 61929 J
Conversion from J to kilojoule
1 J = 10^-3 kJ
61929 J =
Total energy change, ΔE = 61.929 kJ
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