Question

Give Reasons:
1. Platinum, gold and silver are used to make jewellery.
2. Sodium, Potassium and lithium are stored under oil.
3. Aluminium is a highly reactive metal, yet it is used to make utensils for cooking.
4. Carbonate and sulphide ores are usually converted into oxides during the process of extraction.

Answer 1

Complete step by step solution:
Let’s discuss all the points one by one:

1. Hint: The properties required for good jewellery are that it should be lustrous and should have property of molding into any kind of design easily.

Reason: And Reason for using platinum, gold and silver in jewellery making is that they have following properties:
a. They are highly lustrous metals.
b. They are resistant to corrosion.
c. They are highly malleable and ductile so can be transformed into any shape or design

And these are the properties which were required so that is why gold silver and platinum are used to make jewellery.

2. Hint: The common property between sodium, potassium and lithium is that they are highly reactive in oxygen and carbon dioxide.

Reason: Reason behind storing sodium, potassium and lithium in oil is that oil prevents their reaction with oxygen, moisture and carbon dioxide of air. So oil basically prevents them from reacting.

3. Hint: Aluminium metal forms a thin layer of aluminium oxide on its surface under the action of moist air.

Reason: Reason behind using aluminium metal for making utensils for cooking is that it forms a thin layer of aluminium oxide on its surface when it is in moist air, so this layer protects the metal from corrosion. And aluminium is also cheap and easily available. And it is also malleable and ductile. So this is the reason why it is used for making utensils.

4. Hint: We will always use those methods for extraction in which it is easy to react and process becomes easy. It is easy to reduce oxides than that of carbonates or sulphides

Reason: Carbonates and sulphide ore are usually converted into oxides during the process of extraction because it is easy to extract metal from its oxide ore by reduction reaction as compared to carbonate or sulphide ore.

Note:
Always look at the properties of the metal or element and then compare it with why it is used for this purpose.