Assertion: The ionisation energy decreases as we go from left to right in a period.

Reason: The nuclear charge increases as we go from left to right in a period but the number of shells remain the same in a period.

Both assertion and reason are true and the reason is the correct explanation for the assertion.

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Both assertion and reason are true but the reason is not the correct explanation for the assertion.

No worries! We‘ve got your back. Try BYJU‘S free classes today!

The assertion is true but the reason is false.

No worries! We‘ve got your back. Try BYJU‘S free classes today!

The assertion is false but the reason is true.

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Open in App

Solution

The correct option is D
The assertion is false but the reason is true.

The factors for ionisation energy are the size of the atom and effective nuclear charge. The ionisation energy increases as we go from left to right in the period as the nuclear charge increases as we go from left to right in the period, but the number of shells remains the same therefore the ionisation energy increases. Therefore, the reason which is given here is true but the assertion given to us is false.

Suggest Corrections

Similar questions

Q. Read the assertion and reason carefully to mark the correct option out of the options given below:

(a)If both assertion and reason are true and the reason is the correct explanation of the assertion.

(b)If both assertion and reason are true but reason is not the correct explanation of the assertion.

(c)If assertion is true but reason is false.

(d)If assertion is false but reason is true.
Assertion: Ionisation enthalpies for early actinoids are lower than that for early lanthanoids.
Reason: 5f electrons more effectively shielded from the nuclear charge than the 4f electrons
of the corresponding lanthanoids.

Q. Assertion: C₄ – photosynthetic pathway is more efficient than C₃ pathway Reason: Photorespiration is suppressed in C₄ plants

Q. Assertion: Magnesium is important in carbohydrate and protein metabolism. Reason: Mg²⁺ is involved in the synthesis of Nucleic acids.

Q. (i)
Assertion: A circle is not a rectilinear figure.
Reason: A figure formed by straight lines only is called a rectilinear figure.
(a) Both Assertion and Reason are true and Reason is a correct explanation of Assertion.
(b) Both Assertion and Reason are true but Reason is not a correct explanation of Assertion.
(c) Assertion is true and Reason is false.
(d) Assertion is false and Reason is true.
(ii)
Assertion: All right angles are equal to one another.
Reason: A unique line passes through a single point.
(a) Both Assertion and Reason are true and Reason is a correct explanation of Assertion.
(b) Both Assertion and Reason are true but Reason is not a correct explanation of Assertion.
(c) Assertion is true and Reason is false.
(d) Assertion is false and Reason is true.

Assertion: Area of the triangle whose
vertices are $A (\frac{- 3}{2}, 3), B (6, - 2)$ and $C (- 3, 4)$ is 0
Reason : The points A, B and C are collinear

Join BYJU'S Learning Program

Assertion: The ionisation energy decreases as we go from left to right in a period. Reason: The nuclear charge increases as we go from left to right in a period but the number of shells remain the same in a period.

Assertion: The ionisation energy decreases as we go from left to right in a period.

Reason: The nuclear charge increases as we go from left to right in a period but the number of shells remain the same in a period.