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Question
From the symbol `""_15^31"P"`, state :
(i) mass number of phosphorus,
(ii) atomic number of phosphorus, and
(iii) electron configuration of phosphorus.
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Solution
(i) Mass no. = 31
(ii) Atomic no. = 15
(iii) Electronic configuration: (2, 8, 5)
That is,
\[\ce{\underset{2}{K} \underset{8}{L} \underset{5}{M}}\]
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