---
title: "NCERT Solutions for Class 8 Science Chapter 7 Exercise 7.2"
url: https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-2
dateModified: 2026-10-07T16:14:45+00:00
---

# NCERT Solutions for Class 8 Science Chapter 7 Exercise 7.2

Chapter 7: Particulate Nature of Matter. Every question from Exercise 7.2, with full working and the final answer.

Free PDF (13 pages): https://www.swavid.com/api/seo/pdf/ncert/science/class-8/swavid-ncert-solutions-class-8-science-chapter-7-particulate-nature-of-matter-7cb91bb328.pdf

## Activity 7.2: Let us perform

### Question 1

*2 marks · Very short answer*

Are the units of chalk obtained in this manner considered the smallest units of chalk?

**Solution**

1. The tiny units of chalk obtained by continuous grinding are the basic building blocks of chalk.
2. However, they are still made up of millions of constituent particles and can be broken down further until we reach the ultimate constituent particles.

**Answer:** No, the units obtained by grinding are not the absolute smallest units, as they are further made up of constituent particles.

> Common mistake: Thinking that visible fine powder is the smallest possible unit of matter.

### Question 2

*2 marks · Very short answer*

Does the water taste sweet?

**Solution**

1. When two teaspoons of sugar are added to water without stirring, sugar settles at the bottom and the top layer of water remains plain.
2. Therefore, the water from the top layer does not taste sweet initially.

**Answer:** No, the water from the top layer does not taste sweet before stirring.

> Common mistake: Assuming sugar mixes instantly throughout the water without stirring.

### Question 3

*2 marks · Very short answer*

What difference in taste do you notice? Does it taste sweet?

**Solution**

1. After stirring the water completely, the sugar dissolves and spreads uniformly throughout the solution.
2. As a result, a spoonful of water from the top layer tastes sweet due to the presence of dissolved sugar particles.

**Answer:** Yes, after stirring, the top layer of water tastes sweet because the sugar particles dissolve and spread throughout the solution.

> Common mistake: Thinking sugar disappears completely rather than breaking into constituent particles.

## Related pages

- [All Chapter 7 NCERT solutions](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions)
- [Exercise 7.1](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-1)
- [Exercise 7.3](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-3)
- [Exercise 7.4](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-4)
- [Exercise 7.6](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-6)
- [Exercise 7.7](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-7)
- [Exercise 7.8](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-8)
- [Exercise 7.9](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-9)

Solutions written by SwaVid, a personal AI tutor for Class 6 to 10 Maths and Science. Practise this chapter free: https://www.swavid.com/start/student