Careers360 Logo
JEE Main Form Correction 2024 Session 2 (Closed) - Last Date, Procedure, Guidelines, Fee

Anomalous Behaviour of Lithium - Practice Questions & MCQ

Edited By admin | Updated on Sep 18, 2023 18:35 AM | #JEE Main

Quick Facts

  • Anomalous Behaviour of Lithium is considered one the most difficult concept.

  • 38 Questions around this concept.

Solve by difficulty

Which of the following reaction is correct?

Concepts Covered - 0

Anomalous Behaviour of Lithium

Anomalous Behaviour of Lithium: The anomalous behaviour of lithium is due to the

  1. Exceptionally small size of its atom and ion
  2. High polarising power.

As a result, there is increased covalent character of lithium compounds which is responsible for their solubility in organic solvents. Further, lithium shows diagonal relationship to magnesium which has been discussed subsequently.

Points of Difference between Lithium and other Alkali Metals

  • Lithium is much harder. Its m.p. and b.p. are higher than the other alkali metals.
  • Lithium is least reactive but the strongest reducing agent among all the alkali metals. On combustion in air it forms mainly monoxide, Li_2O and the nitride, Li_3N unlike other alkali metals.
  • LiCl is deliquescent and crystallises as a hydrate, LiCl.2H_2O whereas other alkali metal chlorides do not form hydrates.
  • Lithium hydrogencarbonate is not obtained in the solid form while all other elements form solid hydrogencarbonates.
  • Lithium unlike other alkali metals forms no ethynide on reaction with ethyne.
  • Lithium nitrate when heated gives lithium oxide, Li_2O, whereas other alkali metal nitrates decompose to give the corresponding nitrite.
  • LiF and Li_2O are comparatively much less soluble in water than the corresponding compounds of other alkali metals.

Points of Similarities between Lithium and Magnesium

  • Both lithium and magnesium are harder and lighter than other elements in the respective groups.
  • Lithium and magnesium react slowly with water. Their oxides and hydroxides are much less soluble and their hydroxides decompose on heating.
  • The oxides, Li_2O and MgO do not combine with excess oxygen to give any superoxide.
  • The carbonates of lithium and magnesium decompose easily on heating to form the oxides and CO_2.
  • Both LiCl and MgCl_2 are soluble in ethanol.
  • Both LiCl and MgCl_2 are deliquescent and crystallise from aqueous solution as hydrates.

"Stay in the loop. Receive exam news, study resources, and expert advice!"

Get Answer to all your questions

Back to top