Which of the following statements is correct?

Which of the following reacts with cold water vigorously?

Which of the following non-metals reacts and catches fire on exposure to air?

Which metal is present in haemoglobin?

Which of the following is very hard?

Metals are ______________ conductors of heat and __________________.

Materials can be classified into.....and....

..................litmus paper turns...............when it is dipped in a basic solution.

Copper is.................reactive than zinc.

The oxides of metals are...........in nature

Generally, non-metals react with acids.

Coal can be drawn into wires.

Oxides of non-metals and metals are acidic in nature.

Some metals react with sodium hydroxide to produce hydrogen gas.

Iron is used in constructing bridges and houses

Name the property which enables metals to be drawn into wires.

Write physical properties of metals.

Name the metal
(a) which reacts with dilute hydrochloric acid to produce hydrogen gas.
(b) which does not react with dilute hydrochloric acid.

Some non-metals like phosphorus are kept in water to protect them from atmospheric oxygen. Write the property of non-metals utilised here.

Which metal reacts neither with cold water nor with hot water?

Give reasons for the following:
(a) Aluminium foils are used to wrap food items.
(b) Immersion rods for heating liquids are made up of metallic substances.
(c) Copper cannot displace zinc from its salt solution.
(d) Sodium and potassium are stored in kerosene.

We should not store food stuff in container which is made up of metals such as copper, zinc, aluminium, etc. Why?

If a blacksmith beats an iron piece with hammer. Do you think, will it Change its shape? If yes, would you expect a similar Change in woodlog on beating?

In what form magnesium is found in plants?

Shikha bought a new iron container and kept blue copper sulphate solution in it. Next day, she found that blue colour of copper sulphate solution fades and iron container becomes porous. She went to the shopkeeper and complaint that iron container is not of good quality. But the shopkeeper argued that container is of good quality and he is not giving her money back, By chance, her friend Mohan came there and asked the matter, and told that the container is of good quality and you have kept the wrong substances in it, so fault is all yours.
On the basis of the above passage answer the following questions.
(a) Why the container becomes porous when blue copper sulphate solution is kept in it?
(b) What qualities are exhibited by Mohan.

Iron is more reactive than copper. Can you write an activity to show this?

Metals are malleable and ductile. They possess such properties which make them useful for a number of purposes, e.g. in making coins, jewellery, electrical wires, etc. For different requirements, different metals are used. It depends on the nature of metals. Now give the answer of the following questions.
(a) Give two reasons why gold is used in making jewellery?
(b) If you have to select the metal among copper, aluminium and silver for the transmission of electricity, which one would you prefer and why?
(c) Between silver and copper, which is the better conductor of heat?
(d) Generally, silver foils are used for the decoration of sweets. Are they harmful for us? If yes, then in what manner?