Question

What is the enthalpy of a mixture having 10% of A with enthalpy 10 J, 30% of B with enthalpy 30 J, and 60% of C with enthalpy 25 J?

(a) 21 J

(b) 25 J

(c) 27 J

(d) 28 J

I had been asked this question in examination.

The above asked question is from Heat of Solution, Dissolution and Mixing in division Energy Balances that Include the Effects of Chemical Reaction, Ideal Processes, Efficiency and the Mechanical Energy Balance and Heats of Solution and Mixing of Basic Chemical Engineering

Answer 1

Right option is (b) 25 J

The explanation: Heat capacity of mixture = 0.1*10 + 0.3*30 + 0.6*25 = 1 + 9 + 15 = 25 J.