Question 4 - Assertion Reasoning questions (MCQ) - Chapter 5 Class 10 - Periodic Classification of Elements

Assertion (A): The atomic and ionic radii generally decrease towards right in a period.

Reason (R): The ionisation enthalpy increases on moving towards left in a period.

Answer

• As we move from left to right in a period, the ionic and atomic radii decrease .
• Ionization enthalpy is the energy required to remove an electron from an atom . As we move from left to right in a period, as the atomic size decreases, and ionization enthalpy increases .

Thus,

• Assertion is true.
• Reason is false.

Therefore, the correct option is (c) Assertion is true but Reason is false