Metals and Non-Metals — Science STD 10 — Question

Which of the following statements about the Modern Periodic Table is correct:

1. It has 18 horizontal rows known as Periods.
2. It has 7 vertical columns known as Periods.
3. It has 18 vertical columns known as Groups.
4. It has 7 horizontal rows known as Groups.

The number of carbon atoms in the organic compound named as 2,2-dimethylpropane is:

A cyclic hydrocarbon having carbon-carbon single bonds as well as carbon-carbon double bonds in its molecule is:

Stainless steel is very useful material for our life. In stainless steel, iron is mixed with:

A molecule of ammonia (NH₃) has:

When a vegetable oil is treated with hydrogen in the presence of nickel (or palladium) catalyst, it forms a fat. This is an example of:

1. Anodising reaction.
2. Substitution reaction.
3. Displacement reaction.
4. Addition reaction.

Match the following with the correct response:

Column A	Column B
(i) Welding	(a) Ethyl alcohol
(ii) Fuel in a spirit lamp	(b) Ester
(iii) Lime water turns milky	(c) Carbon dioxide
(iv) Fruity smell	(d) Ethyne and oxygen

In stainless steel alloy, iron metal is mixed with:

Plaster of Paris is prepared by heating one of the following to a temperature of 100°C. This is:

1. CaSO₃.2H₂O
2. CaCl₂.2H₂O
3. CaCO₃.2H₂O
4. CaSO₄.2H₂O

A student puts one big iron nail each in four test tubes containing solutions of zinc sulphate, aluminium sulphate, copper sulphate and iron sulphate. A reddish brown coating was observed only on the surface of iron nail which was put in the solution of: