Question

Formation of a compound is-
(A) Physical change
(B) Temporary change
(C) Chemical change
(D) Reversible change

Answer 1

Hint: A compound can be defined as a chemical substance that is composed of different identical molecules that are made up of atoms from $1$ or more elements bound together with chemical bonds.

Complete step by step answer:
On the basis of bonding between elements, there are $4$ types of compounds. When metals react with non-metals, ionic compounds are formed via ionic bonding and when non-metals are reacted together, covalent compounds are formed via covalent bonding. A Molecule is the smallest part of the compound that contains all the properties.
A Physical change is a change in which only the physical properties of matter change like state of matter, colour, odour, solubility, etc. all are the parameters of physical change. In a physical change, the composition or the chemical nature of matter does not change. During a physical change, the molecules are rearranged without changing the internal composition. A physical change does not affect the chemical property of the matter.
A reversible change is a chemical change where no new compound or species is generated or created. Only the physical properties of the material change which can be recovered by reversing the conditions.
Chemical changes are those changes in which elements are chemically combined and the molecular composition is completely changed and a new product is formed. The changes that occur in a Chemical change are irreversible and permanent. Change in temperature, the formation of a precipitate, formation of bubbles are parameters of chemical change.
Therefore, we can say that formation of a compound is a chemical change.

So, the correct answer is Option C.

Note: While Temporary changes are those changes which occur only for a short time. Temporary changes are reversible changes e.g. melting of ice. Permanent changes are those changes that are not reversible. They occur for a longer time period.