Question

What is true when an ion is formed?

A There is an unequal number of electrons and neutrons.
B There is an unequal number of electrons and protons.
C The atom loses one or more protons.
D The atom loses one or more neutrons.

Answer 1

Answer : The correct option is, (B) There is an unequal number of electrons and protons.

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 Na has equal number of protons and electrons i.e 11 but
`Na^+` ion has unequal number of protons and electrons that means it has 11 number of protons and 10 number of electrons.

Hence, the correct option is, (B)

Answer 2

Answer: The correct answer is Option B.

Step-by-step explanation:

Atomic number is defined as the number of protons or number of electrons that are present in an element.

In a neutral element, the number of protons and electrons remains the same.

But, when the number of electrons and protons differ, it leads to the formation of ionic species. When an atom gains electrons, it will lead to the formation of negatively charged ion known as anion and when an atom looses electrons, it will lead to the formation of positively charged ion known as cation.

Thus, the correct answer is Option B.