Chapter 1.1, Problem 1.2BFP

(a)

Interpretation Introduction

Interpretation:

Whether the formation of clouds in the sky is a physical change or a chemical change is to be determined.

Concept introduction:

The change that takes place only in state or appearance and not in the composition is known as physical change. The atoms or the molecules of a substance do not change their identity when a substance undergoes a physical change. The change accompanied by the change in the physical properties only is classified as physical change. The substance remains the same before and after the change. For example, the melting of ice is a physical change.

$\text{Ice}\left(\text{water}\right)\to \text{liquid}\left(\text{water}\right)$

The change that takes place in the composition is known as chemical change. The atoms or the molecules of the substance rearrange and transformed into a new substance. For example, the burning of paper is a chemical change.

$\text{Paper}\left(\text{cellulose}\right)\to \text{ash}\left(\text{carbon}\right)$

(b)

Interpretation Introduction

Interpretation:

Whether the souring of old milk is a physical change or a chemical change is to be determined.

Concept introduction:

The change that takes place only in state or appearance and not in the composition is known as physical change. The atoms or the molecules of a substance do not change their identity when a substance undergoes a physical change. The change accompanied by the change in the physical properties only is classified as physical change. The substance remains the same before and after the change. For example, the melting of ice is a physical change.

$\text{Ice}\left(\text{water}\right)\to \text{liquid}\left(\text{water}\right)$

The change that takes place in the composition is known as chemical change. The atoms or the molecules of the substance rearrange and transformed into a new substance. For example, the burning of paper is a chemical change.

$\text{Paper}\left(\text{cellulose}\right)\to \text{ash}\left(\text{carbon}\right)$

(c)

Interpretation Introduction

Interpretation:

Whether melting of butter is a physical change or a chemical change is to be determined.

Concept introduction:

The change that takes place only in state or appearance and not in the composition is known as physical change. The atoms or the molecules of a substance do not change their identity when a substance undergoes a physical change. The change accompanied by the change in the physical properties only is classified as physical change. The substance remains the same before and after the change. For example, the melting of ice is a physical change.

$\text{Ice}\left(\text{water}\right)\to \text{liquid}\left(\text{water}\right)$

The change that takes place in the composition is known as chemical change. The atoms or the molecules of the substance rearrange and transformed into a new substance. For example, the burning of paper is a chemical change.

$\text{Paper}\left(\text{cellulose}\right)\to \text{ash}\left(\text{carbon}\right)$