Reacting 10.0 mL of H2(g) with 10.0 mL of C2H4(g) produces 10.0 mL of C2H6 at 1.5 atm. If the reaction produces 3.1 kJ of heat and the decrease in volume requires the heat surroundings do 7.6 J of work on the gases, what is the change in internal energy of the gases?

the change in internal energy of the gases is  -3.0924 KJ

Explanation:

The computation of the change in internal energy of the gases is as follows;

Given that

Q = -3.1 KJ

= -3100 J

It is negative as the heat is lost from the mixture

And,

W = + 7.6 J

It is positive as the work is done in the mixture

Now we use the following equation

Delat E = Q + W

= -3100 J + 7.6 J

= -3092.4 J

= -3.0924 KJ

Hence, the change in internal energy of the gases is  -3.0924 KJ