Metals and Non-...

Why the grills of doors and windows are always painted before used?

Identify the metal that occurs in both combined and native state in nature.

What will you observe when copper ($$Cu$$) is kept in hydrochloric acid ($$HCl$$)?

The non-metal which is hard is :

Corrosion of metals can be prevented when contact between metal and .......... is cut off.

Metals generally react with water to form corresponding oxides or hydroxides and:

Metal which does not react even with steam is :

Door locks are made of metals because metals:

Corrosion of iron forms:

1 kg of iron occupies less space compared to 1 kg of sponge. Why?