Lithium

Lithium is an alkali metal with the atomic number 3 and an atomic mass of 6.941 g/mol. It consists of 3 protons, 3 electrons, and approximately 4 neutrons. Lithium is an alkali metal characterised by its softness, flammability, and high reactivity, readily forming hydroxides. Its low density makes it the least dense solid element at standard conditions.

1.0Introduction 

Lithium was first discovered in the mineral petalite by Johan August Arfwedson in 1817, with Sir Humphry Davy and W.T. Brande later isolating the element. Though rare, lithium constitutes about 0.0007% of the Earth's crust in its mineral form. Its compounds have long been used in specific types of glass and porcelain. In recent years, lithium has gained increased importance for its role in dry-cell batteries and nuclear reactors. Additionally, certain lithium compounds are prescribed to treat bipolar disorder.

General properties of Lithium

2.0Physical Properties of Lithium

Property

Description

State at Room Temperature

Solid element

Softness

Very soft metal

Colour

Silver-white or grey

Density

Least dense solid metal; lower than water

Lightness

Lightest solid metal

Group Classification

Group 1 (alkali metals)

Atomic Number

3

Atomic Mass

6.941 g/mol

Melting Point

180.2 °C

Boiling Point

1342 °C

Specific Heat

3582 J/kg·K

Thermal Conductivity

84.8 W/m·K

3.0Chemical Properties Of Lithium

Because of its  reactivity, lithium reacts both with organic and inorganic substances. Because of its placement in Group 1 of the periodic table, lithium has a high degree of reactivity, particularly when it comes to non-metals like oxygen, nitrogen, and halogens, as seen by the following reactions.

  • Reaction with Air: Lithium burns bright red when it comes into contact with air (O2); the main byproduct is lithium monoxide.(Li2O).

           4Li + O₂ -> 2Li₂O

  • Reaction with Acids: Lithium oxide (LiO) and acids such as hydrochloric acid (HCl) combine to produce water and lithium chloride (LiCl).

           Li₂O → 2LiCl + H₂O + 2HCl

  • Reaction with Water: Lithium hydroxide (LiOH) and hydrogen gas are also produced when lithium oxide (Li2O) and water combine.

          4LiOH + H₂ = 2Li₂O + 2H₂O

  • Reaction with Nitrogen: Lithium is the only alkali metal that directly reacts with nitrogen (N₂) to form lithium nitride (Li₃N).

           6Li + N₂ → 2Li₃N

  • Reaction with Hydrogen: Lithium reacts quickly with hydrogen gas (H₂) to produce lithium hydride (LiH). 2Li + H₂ → 2LiH
  • Reaction with Carbon: When lithium reacts with carbon dioxide (CO₂), it forms lithium carbide (Li₂C₂) and lithium oxide (Li₂O).10Li + 2CO₂ → Li₂C₂ + 4Li₂O
  • Reaction with Halogens: Due to the small size of its cation (Li⁺), lithium reacts with halogens (X₂, where X can be fluorine, chlorine, bromine, or iodine) to form ionic halides (LiX).2Li + X₂ → 2LiX (X = F, Cl, Br, I)

4.0Uses of Lithium

  • Lithium-ion batteries:

Rechargeable batteries, which power gadgets like cell phones, computers, digital cameras, and electric cars, are the main application for lithium.

Non-rechargeable batteries for gadgets like toys, clocks, and heart pacemakers also include lithium.

  • Alloys:

Lithium-Aluminum Alloys: Used in high-speed trains, bicycle frames, and airplanes, these alloys increase the strength and decrease the weight of aluminum.

Magnesium-lithium alloys: Armour plating is done using magnesium-lithium alloys that have been strengthened.

  • Ceramics and Glass:

Lithium oxide enhances the qualities of unique glasses and glass ceramics.

  • Materials that Hygroscopic:

One of the materials that is most hygroscopic is lithium chloride (LiCl). It is utilized in industrial drying systems and air conditioning systems.

  • Lubricants:

Lithium Stearate: This lubricant can be used for any purpose and works especially well at high temperatures.

  • Applications in Medicine:

Lithium carbonate is a common ingredient in drugs used for  treatment of  bipolar disorder and manic depression.

  • Storage of Hydrogen:

Lithium Hydride (LiH): A fuel source that can be utilized to store hydrogen.

Frequently Asked Questions

Lithium is stored in a non-reactive environment, typically under oil or in an inert atmosphere, to prevent it from reacting with moisture in the air.

Lithium has a very high electrochemical potential, making it ideal for use in rechargeable lithium-ion batteries. These batteries power most modern electronics and electric vehicles due to their high energy density and long life.

Lithium reacts with water and produces lithium hydroxide and hydrogen gas. This exothermic reaction releases heat and can cause the hydrogen to ignite under certain conditions.

Lithium is used to strengthen and lighten alloys. For example, lithium-aluminium alloys are used in aerospace applications, while magnesium-lithium alloys are used in armour-plating

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