Question

In order for an atom to be neutral (i.e. have no charge), it must have the same number of ______ as it has protons. a. neutrons b. electrons c. neutrons and electrons d. molecules e. None of the above.

Answer 1

Answer : The correct option is, (b) There is a same number of electrons.

Explanation :

For the neutral atom, the number of protons and electrons are equal. But, they are unequal when the atoms present in the form of ions or the atom has some charges.

When an unequal number of electrons and protons then it leads to the formation of ionic species.

Ion : An ion is formed when an atom looses or gains electron.

When an atom looses electrons, it will form a positive ion known as cation.

When an atom gains electrons, it will form a negative ion known as anion.

For example : The neutral atom Mg has equal number of protons and electrons i.e 12 but $Mg^{2+}$ ion has unequal number of protons and electrons that means it has 12 number of protons and 10 number of electrons.

Hence, the correct option is, (B) electrons