Question

When hydrogen burns in oxygen, water is formed. The type of chemical change involved is:
A. combustion
B. evaporation
C. displacement
D. decomposition

Answer 1

Hint: When hydrogen burns in oxygen from the air and it thereby transfers energy to the surroundings in the form of light and heat.

Complete step by step answer:
The burning of hydrogen gas with oxygen gas to form water molecules is a combustion reaction because it is the combustion of hydrogen in the presence of oxygen gas. The type of chemical change involved is combustion, because the oxygen pressure is the burning of the combustion reactant.
The reaction for the same is;
 ${{\text{H}}_2}{\text{ + }}\dfrac{1}{2}{{\text{O}}_2}{\text{ }} \to {\text{ }}{{\text{H}}_2}{\text{O}} $

So, the correct answer is Option A.

Additional Information:
A combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat. Combustion is the scientific term for burning, in a combustion reaction, a substance reacts with oxygen from the air and transfers energy to the surroundings in the form of light and heat. The products of a combustion reaction are called oxides.
Combustion reactions must include O2 as one reactant. A familiar example of a combustion reaction is a lighted match. When a match is struck, friction heats the head to a temperature at which the chemicals react and can produce more heat in the air, and they burn with a flame.

Note: Chemical reactions are used everywhere in the world, may it be cracking of petroleum or turning fat or oil and it is widely used in the soap industry. In addition to these basic combustion reactions, many other such reactions are employed in a wide range of industries. For example, the space industry is known to exploit the combustion reaction between hydrogen and oxygen for the generation of clean energy in rocket ships.