Give reasons for the following: 1. Noble gases show least reactivity. 2. Nucleus of an atom is heavy and positively charged. 3. Ions are more stable than atoms. 4. The chemical properties of isobars are not similar. 5. Electrons are known as planetary electrons.

Asked by Sthitaprajna Mishra | 17th Feb, 2014, 08:46: PM

Expert Answer:

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Solution of your first query,

In any kind of chemical reactivity, the valence shell is involved. Each element required to gain, lose or share electron to complete its valence shell capacity. But in the case of noble gases, their valence shell is already completely filled to its maximum capacity. All have their octet completed except helium in which duplet is completed. Hence, all the noble gases show least reactivity.


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Answered by  | 18th Feb, 2014, 10:38: AM

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