Same chapter3 marksDifficulty: Medium
An element has two isotopes of mass numbers 35 and 37 present in the ratio 3 : 1. Calculate its average atomic mass.
Atomic Structure and Chemical Bonding
3 marksDifficulty: Medium
Why do noble gases not usually take part in chemical reactions?
Original Khojo Papers practice question — not from a past board paper.
Answer
Their outermost shells are completely filled — two electrons for helium and eight for the rest — which is the most stable arrangement an atom can have. They therefore have no tendency to gain, lose or share electrons, and it is the movement of electrons that makes a chemical reaction.
No citable source has been recorded for this record. Treat it as practice material, not as fact.
Explanation
Some compounds of xenon and krypton have been made under extreme conditions.
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