NIOS Class 10 Science Activity 27.1 Solution |Metals and Non-Metals

In NIOS Class 10 Science Chapter 27- Metals and Non-Metals, Activity 27.1 helps students understand one of the most important physical properties of metals – Metallic Lustre. In this activity, we collect samples of iron, copper and aluminium and observe their colour and appearance before and after cleaning their surface with sandpaper.

Metals and Non-Metals Activity Solution

This activity is based on the NIOS Class 10 science and technology (212) Chapter 27- Metals and Non-Metals Module 6- Natural Resources.

 

NIOS Class 10 Science Activity 27.1

Aim

To observe the colour and appearance of metal samples

Materials Required

   1. Piece of iron

   2. Piece of copper

   3. Piece of aluminium

   4. Sandpaper

   5. Notebook and pen

Procedure

We collect small samples of iron, copper and aluminium and observe the colour and appearance of each metal sample.

Now we clean the surface of each metal piece using sandpaper and observe the sample again.

We write both observations before and after cleaning.

Observation

Metal	Colour before cleaning	Colour after cleaning	appearance
Iron	Dull grey	Shiny grey	Metallic lustre visible
Copper	Reddish brown	Bright reddish	Surface become shiny
Aluminium	Dull silver	Bright silver	Smooth and shiny

 

Explanation

Metals usually have a shiny surface known as metallic lustre. However, when metals are exposed to air and moisture, a thin layer of oxide or dust forms on the surface, making them dull.

When the surface is rubbed with sandpaper, the layer is removed, and the original shiny metal surface becomes visible. This is metallic lustre.

Conclusion

We can conclude that iron, copper and aluminium are metals and show metallic lustre. This is an important property of metals.

MCQs Based on Activity 27.1

Q1. Which property of metals is discussed in this activity?

(a)       Hardness

(b)      Metallic lustre

(c)       Density

(d)      Brittleness

Correct answer – (b) Metallic lustre

Q2. Which material is used to clean the metal surface in this activity?

(a)       Water

(b)      Soap

(c)       Sandpaper

(d)      Cloth

Correct answer – (c) -Sandpaper

Q3. Which metal has a reddish colour?

(a)       Iron

(b)      Copper

(c)       Aluminium

(d)      Zinc

Correct answer – (b) – copper

Q4. Aluminium generally appears:

(a)       Yellow

(b)      Silver

(c)       Red

(d)      Black

Correct answer – (b ) -silver

Q5. Metals become dull mainly due to:

(a)       Heat

(b)      Dust and oxide layer

(c)       Sunlight

(d)      Moisture

Correct answer – (b) dust and oxide layer

Frequently Asked Questions

Q1. What is metallic lustre?

Answer – Metallic lustre is the shiny appearance of metals when light reflects from their surface.

Q2.  Why do metals become dull after some time?

Answer – Metals become dull because of oxidation, dust and moisture present in the air.

Q3. Why was sandpaper used in activity 27.1?

Answer – Sandpaper is used to remove the outer dull layer from the metals.

Q4. Which metals were used in this activity?

Answer – Iron, copper and aluminium were used in this activity.

Q5. What property of metals is demonstrated in this activity?

Answer – Metallic lustre