Question 46

Water vapor is produced when hydrogen burns in air.

When hydrogen combusts in air, it reacts with oxygen to produce water vapor as the primary product of the reaction.

A) Carbon monoxide

Carbon monoxide is produced from the incomplete combustion of carbon-containing materials. Since hydrogen does not contain carbon, it cannot produce carbon monoxide when burned in air.

B) Carbon dioxide

Carbon dioxide is generated from the complete combustion of hydrocarbons or carbon-based fuels. As hydrogen is a non-carbon fuel, burning it in air will not yield carbon dioxide.

C) Nitrous oxide

Nitrous oxide is typically formed from reactions involving nitrogen and oxygen at high temperatures, such as during combustion processes involving fuels containing nitrogen. Hydrogen combustion does not produce nitrous oxide.

D) Water vapor

When hydrogen burns in air, it combines with oxygen to form water vapor, which is the expected and correct product of this reaction.

Conclusion

Water vapor is the definitive product of hydrogen combustion in air, making it the correct answer. Other options fail because they either require carbon-based materials for their production or involve different chemical reactions not applicable to hydrogen combustion.