Chapter 1, Problem 1.4P

(a)

Interpretation Introduction

Interpretation:

Definition of physical and chemical properties is to be stated. Also, whether the attack of yellow-green chlorine gas on silvery sodium metal to form white crystals of sodium chloride (table salt) is a physical property or chemical property 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 substance remains the same before and after the change. Physical change brings change in physical properties only. 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. A chemical change can change physical as well as chemical properties of a substance. For example, the burning of paper is a chemical change.

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

The characteristics that give a unique identity to a particular substance are called properties of a substance. There are two properties of a matter namely chemical properties and physical properties.

(1) Physical properties are the properties that can be identified without changing the composition of the substance. Physical properties include melting point, boiling point, and density.

(2) Chemical properties are the properties that are observed as a result of chemical change or chemical reaction. Chemical properties include acidity, basicity, and flammability.

(b)

Interpretation Introduction

Interpretation:

Definition of physical and chemical properties is to be stated. Also, whether the separation of a mixture of black iron shavings and white sand is a physical property or chemical property 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 substance remains the same before and after the change. Physical change brings change in physical properties only. 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. A chemical change can change physical as well as chemical properties of a substance. For example, the burning of paper is a chemical change.

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

The characteristics that give a unique identity to a particular substance are called properties of a substance. There are two properties of a matter namely chemical properties and physical properties.

(1) Physical properties are the properties that can be identified without changing the composition of the substance. Physical properties include melting point, boiling point, and density.

(2) Chemical properties are the properties that are observed as a result of chemical change or chemical reaction. Chemical properties include acidity, basicity, and flammability.