Question

Please answer this Q
In the B) option -- the last words after neutrons is ( it's nucleus)​

Answer 1

Answer:

I think option a is correct .

Answer 2

Explanation:

as per Aufbau principle

the general Electronic configuration

of 2He 4-->1s2

I. e. the no of electron in helium atom is 2e

since doublet of helium is completed i. e... full filled s orbital so it shows noble gas properties

so here number of electrons is equal to the no of protons

therefore no of protons =2

also as we know

at. mass = no of proton+no of

neutrons .. ,as atomic mass of he is 4

hence

no of neutrons =at mass --no of protons

hence no of protons in nucleus =4--2

=2

hence by all the above conventions it is clear that

option a is correct