The World of Metals and Non metals Class 7 Long Question Answer

The World of Metals and Non metals Class 7 Long Question Answer

The World of Metals and Non metals Class 7 Long Question Answer

Question 1.

Compare and contrast malleability and brittleness with examples.

Answer:

Malleability allows materials like gold and copper to be flattened into sheets without breaking. Brittleness causes materials like glass and sulfur to break when force is applied. Metals are generally malleable, while non-metals are brittle, making each suitable for different uses.

Question 2.

How does sustainability relate to metal usage and recycling?

Answer:

Sustainability involves using metals efficiently and recycling them to minimise resource depletion. Recycling reduces mining impact, conserves energy, and helps maintain long-term ecological balance. Metals like aluminium and steel are widely recycled in sustainable practices.

Question 3.

Explain the significance of galvanisation in protecting infrastructure.

Answer:

Galvanisation prevents rust in steel and iron-based structures, extending their life and reducing maintenance costs. By applying a zinc coating, it creates a barrier against moisture and oxygen, especially useful for bridges, pipes, and construction materials exposed to the elements.