Question

When oxygen reacts with hydrogen, it has the capacity to release 29 kilojoules of energy. Inside a fuel cell, oxygen reacts with hydrogen to produce 23 kilojoules of useful energy. The rest of the energy is lost as heat. What’s the efficiency percentage of the fuel cell?

Answer 1

79%

Step-by-step explanation:

PLATO

further explanation-

useful energy out/total energy in x 100.

substitute the values given in the problem:

23/29 x 100 = 79.31%

≈79%