English Medium कक्षा १० - CBSE Question Bank Solutions

Explain why, though aluminium is more reactive than iron, yet there is less corrosion of aluminium when both are exposed to air.

What is corrosion?

Name any two metals which do not corrode easily.

What is the corrosion of iron known as?

With the help of labelled diagrams, describe an activity to find out the conditions under which iron rusts.

Give the constituents of brass.

Name two metals which resist corrosion due to the formation of a thin, hard and impervious layer of oxide on their surface.

Name five methods of preventing rusting of iron.

What are the constituents of stainless steel?

What are the special properties of stainless steel?

Name an alloy of copper. State its chemical composition and any one use.

Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as?

Explain why, the galvanised iron article is protected against rusting even if the zinc layer is broken.

Name a common metal which is highly resistant to corrosion.

A common metal which is highly resistant to corrosion is ______.

In stainless steel alloy, iron metal is mixed with ______.

If copper is kept exposed to damp air for a considerable time, it gets a green coating on its surface. This is due to the formation of ______.

Brass is an alloy of ______.

No chemical reaction takes place when granules of a rusty-brown solid A are mixed with the powder of another solid B. However, when the mixture is heated, a reaction takes place between its components. One of the products C is a metal and settles down in the molten state while the other product D floats over it. It was observed that the reaction is highly exothermic.

1. What could the solids A and B be?
2. What are the products C and D most likely to be?
3. Write the chemical equation for the reaction between A and B leading to the formation of C and D. Mention the physical states of all the reactants and products in this equation and indicate the heat change which takes place.
4. What is the special name of such a reaction? State one use of such a reaction.
5. Name any two types of chemical reactions under which the above reaction can be classified.

A metal X which is resistant to corrosion is produced by the electrolysis of its molten oxide whereas another metal Y which is also resistant to corrosion is produced by the reduction of its oxide with carbon. Metal X can be used in powder form in thermite welding whereas metal Y is used in making cathodes of ordinary dry cells.

1. Name the metals X and Y.
2. Which of the two metals is more reactive: X or Y?
3. Name one ore or metal X. Also write its chemical formula.
4. Name one ore of metal Y. Also write its chemical formula.
5. Name one alloy of metal X and one alloy of metal Y.