---
title: "NCERT Solutions for Class 8 Science Chapter 7 Exercise 7.8"
url: https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-8
dateModified: 2026-10-07T16:14:45+00:00
---

# NCERT Solutions for Class 8 Science Chapter 7 Exercise 7.8

Chapter 7: Particulate Nature of Matter. Every question from Exercise 7.8, 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 7.8: Let us experiment

### Question 1

*Activity*

What do you observe?

**Solution**

1. Initially, streaks of pink colour spread out from the potassium permanganate grain into the water.
2. With the passage of time, the entire bulk of water acquires a uniform pink colour due to the constant motion of water particles.

**Answer:** Initially streaks of pink colour spread out, and finally the entire bulk of water acquires a uniform pink colour.

> Common mistake: Thinking that stirring is required for the pink colour to spread throughout the water.

## 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 7.2](https://www.swavid.com/science/class/8/chapter/particulate-nature-of-matter/ncert-solutions/exercise-7-2)
- [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 7.9](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