Question

Identify all the signs of a chemical change in the description below:

A clear liquid is placed in a beaker and heated. As the liquid is heated, bubbles form and, gradually, the liquid decreases in the container.

Answer 1

When a substance undergoes changes in its chemical composition or combines with another substance to form a new substance is referred to as chemical change. In contrast, physical change is defined as the change in appearance or state of matter and not the chemical composition of the substance.

Step-by-step explanation:

When a clear liquid is boiled or heated, the kinetic energy of the molecules increases, and the evaporation of the liquid takes place faster. For example, evaporation is a type of physical change, in which the liquid is heated to form bubbles or vapors. These vapors rise in the air and decrease the volume of the liquid. In this process, the liquid has only changed its state of matter (liquid to gas) and not the chemical composition. Thus, there is no chemical change taking place in the heating of water and only physical change is taking place.