Question

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Answer 1

Answer:

3. It represents a chemical name of an element or a compound.

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Answer 2

Answer:

3. A formula represent a number of atom and molecule of those element in a compound.For example- h20 means 2molecule of hydrogen and 1molecule of oxygen in ratio of 2:1.

4. Variable valency is defined as if any metallic element shows more than one valency, it is called Variable valency. It means that metallic element can lose electron from its inner orbit also.

Example: Fe2+, Fe3+, Cu+, Cu2+, Hg+, Hg2+ etc.

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