An atom is made of 16 protons, 17 neutrons, and 18 electrons. What is the mass number of
this atom?

The mass number of the atom is "33".

According to the question.

Number of protons,

Number of neutrons,

Number of electrons.

As we know the formula,

→

By substituting the values, we get

→                        

→                        

Thus the above response is correct.

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The answer is 33 .

Explanation:

The mass number of an atom is the atomic mass which consists of proton and neutron. This atom has 16 protons and 17 neutrons so it has a mass of 33 :

proton number + neutron number = nucleon number / atomic mass

16 + 17 = 33