Difference between Metals and Non-metals on the basis of Chemical Properties:

1. Formation of Ions:

• Metals lose electrons to form positively charged ions (cations). For example, sodium loses one electron to form Na⁺.
• Non-metals gain electrons to form negatively charged ions (anions). For example, chlorine gains one electron to form Cl⁻.

2. Nature of Oxides:

• Metals combine with oxygen to form basic oxides. Some metals like aluminium and zinc form amphoteric oxides that show both acidic and basic behaviour.
• Non-metals combine with oxygen to form acidic or neutral oxides. For example, sulphur forms SO₂ (acidic oxide) and carbon forms CO (neutral oxide).

3. Reaction with Water:

• Metals react with water to form metal oxides or metal hydroxides and hydrogen gas. Different metals show different reactivities - potassium and sodium react violently with cold water, while copper and silver do not react at all.
• Non-metals generally do not react with water.

4. Reaction with Acids:

• Metals above hydrogen in the reactivity series react with dilute acids to produce salt and hydrogen gas.
• Non-metals do not displace hydrogen from dilute acids.

5. Reaction with Hydrogen:

• Metals generally do not react with hydrogen.
• Non-metals react with hydrogen to form hydrides (like HCl, NH₃, H₂O).

6. Reducing/Oxidising Nature:

• Metals act as reducing agents as they lose electrons.
• Non-metals act as oxidising agents as they gain electrons.