An element ‘M’ has atomic number 12.

(i) Write its electronic configuration and valency.

(ii) Is ‘M’ a metal or a non-metal? Give reason in support of your answer.

(iii) Write the formula and nature (acidic/basic) of the oxide of M.



Atomic number of M = 12


Electronic configuration = 2, 8, 2

Since 2 electrons are present in the outermost shell, valency = 2


Metals lose electrons to become stable(ie., attain noble gas configuration) whereas, non-metals gain electrons to become stable.

‘M’ has a tendency to lose 2 electrons so as to attain noble gas configuration. So, it is a metal.


Oxygen has an electronic configuration 2, 6 which means it gains 2 electrons to become stable. 

Oxide of M - Teachoo.jpg

The chemical formula will be MO .

Metals form basic oxides and non-metals form acidic oxides.

Since M is a metal, the nature of its oxide will be basic.

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