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Question
Draw the atomic diagram of the following element showing the distribution of – protons, neutrons and the electrons in the various shell of the atom.
Calcium – \[\ce{^40_20Ca}\]
[The upper number represent the – mass number and the lower number represent the – atomic number e.g. calcium – mass number = 40, atomic number = 20]
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Solution
Calcium – \[\ce{^40_20Ca}\]
Atomic number Z = p = e = 20
Mass number A = p + n
40 = 20 + n
∴ n = 40 − 20 = 20
Ca
15 = 2, 8, 8, 2
(K, L, M, N)
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