Question

PUUL LIMU MTUMIS Salt solution.
2. When a copper object is exposed to moist air for a long time, then a green coatings
formed on its surface.
(a) What is the material of the green coating?
(b) State whether the green coating is acidic or basic.
3. Sodium metal reacts vigorously with water.
(a) Name the gas evolved when sodium reacts with water.
(b) State whether the solution formed by the reaction of sodium with water is acidic
or basic.
4 Why are metals used for making bells?
5. Why is phosphorous kept under water?
6. Why is iron not deposited over a copper plate when the copper plate is dipped in iron
sulphate solution?​

Answer 1

Answer:

The answers are as follows:

Explanation:

1. it is a mixture of copper carbonate and copper hydroxide.

2.Basic

3. Hydrogen

4.basic

5. Metals are used for ringing bells because they are sonorous.

6. phosphorous is kept under water because it is a very reactive non metal and when exposed to air, catches fire faster. so, to prevent ignition it is stored in water.

7. it is so because iron is more reactive than copper.