Rusting

Q.

How Can Corrosion Be Prevented?

Q. What is rust? What are the two conditions of rusting? [3 MARKS]

Q.

What are the necessary conditions for rust formation in Iron?

1. Presence of air

2. Presence of water

3. Presence of glass

4. Presence of dust

Q.

When some iron objects are kept in moist air for a few days, their surface gets coated with a reddish-brown powdery mass. What is the chemical name given to this mass?

1. Hydrated zinc oxide.

2. Hydrated calcium oxide.

3. Hydrated iron oxide.

4. Hydrated copper oxide.

Q. Iron becomes soft on heating.

1. True
2. False

Q.

what is rusting caused due to?

Q.

Chemical formula of rust

1. ${\mathrm{Fe}}_2{\mathrm{O}}_{3·}{\mathrm{xH}}_2\mathrm{O}$

2. ${\mathrm{ZnCO}}_3$

3. ${\mathrm{CuSO}}_{4·}{\mathrm{xH}}_2\mathrm{O}$

4. ${\mathrm{Na}}_2{\mathrm{CO}}_3$