JEE Main 2022 · 26 Jul · Shift 2 · Chemistry Q69

ChemistrySingle correct+4 / -1Question 69 of 90

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: LiF is sparingly soluble in water.

Reason R: The ionic radius of $\mathrm{Li^+}$ ion is smallest among its group members, hence has least hydration enthalpy.

In the light of the above statements, choose the most appropriate answer from the options given below.

Both A and R are true and R is the correct explanation of A.

Both A and R are true but R is NOT the correct explanation of A.

A is true but R is false.

A is false but R is true.

Answer and worked solution

Official answer: C

Assertion. LiF has a very high lattice enthalpy and is sparingly soluble. True.

Reason. The smallest ion has the highest hydration enthalpy, not the least. False.

(C)

Topics:Alkali metals

JEE Main 2022 · 26 Jul · Shift 2, Chemistry question 69