What are (a) normal elements (b) harmful elements? Give two examp… - Vidyadip

Question

What are (a) normal elements (b) harmful elements? Give two examples of each.

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Answer

The elements of groups 1, 2 and 13 to 17 are called normal elements. These elements have their outermost shell incomplete and are highly reactive. Example: Fluorine (F), Chlorine (Cl) etc.
The elements that give out harmful radiations are called Radioactive Elements. Example: Uranium (U), Potassium (K), etc

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