Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
JEE Main202227 Jul 2022Evening ShiftChemistrys Block ElementsActual

An element A of group 1 shows similarity to an element B belonging to group 2 . If A has maximum hydration enthalpy in group 1 then B is

Options

  1. AMg
  2. BBe
  3. CCa
  4. DSr

Correct answer

A. Mg

Step-by-step solution

Hydration enthalpy is inversely related to the size of the ion. Li + has maximum hydration enthalpy in group 1 due to its small size. Lithium shows diagonal relationship to magnesium. The similarity between lithium and magnesium is particularly striking and arises because of their similar sizes : atomic radii, Li = 152 pm, Mg = 160 pm; ionic radii : Li + = 76 pm, Mg 2+ = 72 pm. The main points of similarity are (I)Both lithium and magnesium are harder and lighter (ii) Lithium and magnesium react slowly with water.

Practice s Block Elements on Quantrex Academy →

More from s Block Elements

First and second ionization enthalpies of lithium are 520 kJ mol ⁻¹ and 7297 kJ mol ⁻¹ respectively. Energy required to convert 3.5 mg lithium (g) into Li ²⁺ (g) [ Li(g) Li ²⁺ (g) 2026The correct set that contains all kinds (basic, acidic, amphoteric and neutral) of oxides is: 2026Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R : Assertion (A) : BeCl 2 and MgCl 2 produce characteristic flame Reason (R) : T 2023Be ( OH ) 2 reacts with Sr ( OH ) 2 to yield an ionic salt. Choose the incorrect option related to this reaction from the following 2023In the given reaction cycle X , Y and Z respectively are 2023The density of alkali metals is in the order 2023Alkali metal from the following with least melting point is 2023Mg NO 3 2 . XH 2 O and Ba NO 3 2 . YH 2 O , represent formula of the crystalline forms of nitrate salts. Sum of X and Y is....... 2023 Full s Block Elements list All JEE Main PYQs