Question

The atomic numbers of nitrogen and phosphorus are 7 and 15 respectively. Write the electronic configuration of each of them and state the group and period to which they belong.

Answer 1

Answer:

Electronic configuration of nitrogen = 2 , 5

electronic configuration of phosphorus = 2 , 8 , 5

number of shells = Number of period.

in nitrogen there are two shells so it belongs to 2nd period.

in phosphorus there are 3 shells so it belongs to 3rd period.

If the number of valence electrons in an element are 1 or 2 .

it will be of 1st or 2nd group .

if the number of valence electrons are more than 2 , then just add 10 to it.

the resulting number will be your group number.

here in nitrogen .

5+10= 15

hence it is from 15th group.

in phosphorus

5+10=15

hence it is from 15 th group.

Explanation:

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