Which of the following representations is correct for an atom X with 28 electrons and...

Physics

JAMB 2017

Which of the following representations is correct for an atom X with 28 electrons and 30 neutrons?

A. \(^{58}_{28}X\)
B. \(^{30}_{28}X\)
C. \(^{28}_{30}X\)
D. \(^{58}_{30}X\)

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Correct Answer: Option A

Explanation

An atom can be represented thus,

\(^{Z}_{A}X\) where Z = mass number

A = atomic number

A = number of proton = number of electrons in a free state = 28

Z = number of protons + number of neutrons = 28 + 30 = 58

\(^{58}_{28}X\)is the representation

There is an explanation video available below.

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