Question

in which of the following sets is the symbol of the element, the number of protons, and the number of electrons given correctly?
zn, 30 protons, 60 electrons
cs, 55 protons, 132.9 electrons
in, 49 protons, 49 electrons
f, 19 protons, 19 electrons

Explanation:

• For a neutral atom, the number of protons equals the number of electrons.
• Zinc (\(Zn\)) has 30 protons. In a neutral \(Zn\) atom, the number of electrons should be 30, not 60.
• Cesium (\(Cs\)) has 55 protons. The number of electrons in a neutral \(Cs\) atom should be 55. Also, the number of electrons (and protons) must be an integer, not a non - integer like 132.9.
• Indium (\(In\)) has 49 protons. In a neutral \(In\) atom, the number of electrons is 49.
• Fluorine (\(F\)) has 9 protons. In a neutral \(F\) atom, the number of electrons should be 9, not 19.

Answer:

In, 49 protons, 49 electrons.