An atom of 118Xe contains___ neutrons?

A) 118 B) 54 C) 64 D) 172 E) 110

An atom of ¹¹⁸Xe contains 64 neutrons.

Explanation:

Number of Protons:

The number of protons present in any atom are equal to the atomic number of that particular atom. Hence, as the atomic number of Xenon is 54 therefore, it contains 54 protons.

Number Neutrons:

The number of neutrons present in atom are calculated as,

# of Neutrons = Atomic Mass - # of protons

As given,

Atomic Mass = 118

# of Protons = 54

So,

# of Neutrons = 118 - 54

# of Neutrons = 64