Class 10 Science Chapter 3 Metals and Non-metals Notes

1. Chemical Properties of Metals

Reaction with Oxygen: Metals react with oxygen to form basic metal oxides.

Metal + Oxygen → Metal Oxide
4Al(s) + 3O2(g) → 2Al2O3(s) [Amphoteric Oxide]
Note: Aluminium and Zinc oxides show both acidic and basic behavior, making them amphoteric oxides.
Reaction with Water: Reactive metals produce metal hydroxides and hydrogen gas.

2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g)↑ + Heat energy

2. Ionic Compounds

Compounds formed by the complete transfer of electrons from a metal to a non-metal are called ionic or electrovalent compounds.

Properties: High melting and boiling points, crystalline solids, soluble in water, and conduct electricity only in molten or dissolved aqueous states.

3. Extraction of Metals (Metallurgy)

Roasting: Heating sulphide ores strongly in the presence of excess air to convert them into oxides.
Calcination: Heating carbonate ores strongly in limited or absent air to convert them into oxides.

CBSE Board Exam Classic

What is Thermite Reaction? The highly exothermic displacement reaction between Iron Oxide ($Fe_2O_3$) and Aluminium powder ($Al$). The heat generated is so intense that the iron is produced in a molten state, which is used to join cracked railway tracks on-site.

Fe2O3(s) + 2Al(s) → 2Fe(l) + Al2O3(s) + Heat

✏️ Complete NCERT Solutions Class 10 Chapter 3

Q1. Why is Sodium kept immersed in kerosene oil?

Answer: Sodium is an exceptionally highly reactive alkali metal. It reacts violently and catch fire instantly if exposed to open atmospheric air or trace moisture. Keeping it completely submerged in kerosene oil creates a barrier that prevents accidental combustion.

Q2. What are amphoteric oxides? Give two examples.

Answer: Metal oxides that display both acidic as well as basic chemical behaviors are called amphoteric oxides. They react with both acids and bases to yield salt and water.
Examples: Aluminium Oxide ($\text{Al}_2\text{O}_3$) and Zinc Oxide ($\text{ZnO}$).

CBSE Class 10 Science Chapter 3: Metals and Non-metals

1. Chemical Properties of Metals

2. Ionic Compounds

3. Extraction of Metals (Metallurgy)

✏️ Complete NCERT Solutions Class 10 Chapter 3