Question

the mass number of an atom is 27 and its atomic number is 13. Therefore, it is composed of
a) 13 protons, 27 neutrons and 14 electrons
b) 13 protons, 14 neutrons and 14 electrons
c) 13 protons, 13 neutrons and 14 electrons
d)13 protons, 14 neutrons and 13 electrons

Answer 1

Answer: correct option is d

Explanation:

In an atom mass number is define as the sum of protons and neutrons

Atomic number is defined as protons or electrons in an atom

So if mass number is 27 , it means atom has 13 protons and 14 neutrons

Number of protons and electrons in an atom is same, so on whole the atom has 13 protons ,13 electrons and 14 neutrons