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a) C and E: They are isotopes i.e atoms of the same element with same atomic number but different mass number
b) Mass number = Atomic number + No. of neutrons
= 7 = 3 + n
7 – 3 = n = 4
johnmulu answered the question on April 7, 2017 at 09:44
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 7, 2017. Answers (1)
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Date posted: April 6, 2017. Answers (1)
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Date posted: April 6, 2017. Answers (1)