The number of electrons in an element X is 15 and the number of neutrons is 16. Which of the following is the correct representation of the element? (a) 31 15 X (b) 31 16 X (c) 16 15 X (d) 15 16 X
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Answer is (a) 31 15 X
Explanation:
Number of protons in an element depicts atomic number. Number of protons and electrons are equal in an element. Hence atomic number is written in subscript whereas mass number is written in the subscript before the symbol of the element.
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