Question

Define the following:
a) physical change=
b)chemical change= ​

Answer 1

$\large\blue{\textsf{✩ Your Answer ✓ }}$

1. A physical change is a change to the physical—as opposed to chemical—properties of a substance. They are usually reversible. The physical properties of a substance include such characteristics as shape (volume and size), color, texture, flexibility, density, and mass.
2. A chemical change occurs when a new substance is formed through a chemical reaction like when fruit ripens or rots. When something undergoes a "chemical reaction" and a new substance is formed as a result, we call this chemical change. ... The iron reacts with water and oxygen to create a new substance — rust.

Answer 2

Reversible change is physical change .

Irreversible change is chemical change