Atomic number of a few elements are given below

(i) 10 (ii) 20


(iii) 7 (iv) 14


(a) Identify the elements


(b) Identify the period to which these elements belong

(a) (i) Neon (Ne) has atomic number 10.

(ii) Calcium (Ca) has atomic number 20.


(iii) Nitrogen (N) has atomic number 7.


(iv) Silicon (Si) has atomic number 14.


(b) Nitrogen and Neon belong to 2nd period. Silicon belongs to 3rd period. Calcium belongs to 4th period.


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