1. The ion of an element has 3 positive charges. Mass number of the atom is 27 and the number of neutrons is 14. What is the number of electrons in the ion? (a) 13 (b) 10 (c) 14 (d) 16
ScienceClass 9CBSEAnswered 27 Mar 2026
Answer
Soln:
Answer is (b) 10 Explanation:
Mass number (A) of the atom = 27 Number of neutron in the atom =14
Number of Electrons=Mass number-Number of neutrons=27-14 Number of electrons= 13
Since ions of the element has 3 positive charges number of electron in the ion is 13-3 which equal 10. Hence the answer is 10
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