How does the reaction of hydrogen and oxygen to produce energy in a fuel cell differ from their interaction during the direct combustion of hydrogen and oxygen?
I.The direct combustion of hydrogen and oxygen produces several different products,whereas the fuel cell produces only water.
II.Much less heat energy is produced in a fuel cell than via direct combustion of hydrogen and oxygen.
III.In the fuel cell,there is an oxidation-reduction reaction between hydrogen and oxygen.In the direct combustion of hydrogen and oxygen,there is no such reaction.
IV.It is much easier to control the hydrogen and oxygen during direct combustion than during their reaction in a fuel cell.

Question

How does the reaction of hydrogen and oxygen to produce energy in a fuel cell differ from their interaction during the direct combustion of hydrogen and oxygen? 
I.The direct combustion of hydrogen and oxygen produces several different products,whereas the fuel cell produces only water.
II.Much less heat energy is produced in a fuel cell than via direct combustion of hydrogen and oxygen.
III.In the fuel cell,there is an oxidation-reduction reaction between hydrogen and oxygen.In the direct combustion of hydrogen and oxygen,there is no such reaction.
IV.It is much easier to control the hydrogen and oxygen during direct combustion than during their reaction in a fuel cell.

Quizplus · Accepted Answer

Combustion can be explosive and leads to unnecessary loss of energy as heat.

How Does the Reaction of Hydrogen and Oxygen to Produce