Question

3v an atom has 7 electrons in its m-shell and contains 18 neutrons in its nucleus. What is its mass number?

Answer 1

➡The electronic Configuration of the element is given as follows :-

K. ( 2 ). , L ( 8 ). , M( 7 ).

⏪Atomic Number :- 17 .

⏪Number of electrons :- 17

⏪Number of protons :- 17

⏪Number of Neutrons :- 18

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✴Mass Number :- No of protons + No. Of Neutrons

== 17 + 1 8 = 35 .

➡The element is Chlorine.