Alkali metals are highly reactive at standard temperature and pressure and readily lose their outermost electron to form cations with charge +1. Most alkali metals have many different applications, such as rubidium and caesium atomic clocks, sodium-vapor lamps, and table salt.

In the case of the Alkali family, each possesses a single electron in its outermost shell, which they want to “give away” to achieve that more stable outer shell, which makes them very reactive with other atoms or compounds that want an additional electron in their outer shell to achieve stability.

Alkali metals are highly reactive due to their low ionization enthalpy. As we move down the group, the reactivity increases. (1) They react with water to form respective oxides or hydroxides. (4) Almost all alkali metals, except Li, react directly with halogens to form ionic halides.

Lithium

Strong Vs Weak Reducing Agent Fluorine gas is known to be a strong oxidizing agent and whereas F- is said to be a weak reducing agent.

But lithium is still considered the strongest reducing agent among all the alkali metals, and this is evidenced by its large and negative reduction potential.

Lithium burns with a strongly red-tinged flame if heated in air. It reacts with oxygen in the air to give white lithium oxide. Lithium is the only element in this Group to form a nitride in this way.

Reaction of lithium with air The result is a shiny silvery surface but this soon tarnishes because of reaction with oxygen and moisture from the air. When lithium is burned in air, the main product is the white oxide lithium oxide, Li2O. Some lithium peroxide, Li2O2, also white, is also produced.

When any substance burns in oxygen it is called a combustion reaction. Potassium (lilac) burns most vigorously followed by sodium (orange-yellow) and then lithium (red), as you might expect.

Lithium gives oxide, sodium gives peroxide, and other alkali metals form superoxides in this . reaction.

Sodium is a very reactive metal, it tends to react with oxygen to form sodium oxide but this is an unstable compound and soon reacts with hydrogen to form sodium hydroxide. Na2O is a sodium oxide formed by the reaction between sodium metal and oxygen of the air at room temperature.

The reaction between sodium and oxygen is called oxidation because electrons are transferred from one atom to another. When sodium reacts with oxygen each sodium atom loses an electron, which means sodium is oxidized, and each oxygen gains two electrons, meaning it’s reduced.

Answer: Sodium when burnt in excess of oxygen gives sodium peroxide .

Reaction with air, water, and hydrogen In ordinary air, sodium metal reacts to form a sodium hydroxide film, which can rapidly absorb carbon dioxide from the air, forming sodium bicarbonate. It is significantly more reactive in air as a liquid than as a solid, and the liquid can ignite at about 125 °C (257 °F).

Sodium can not be stored in water because Reaction of sodium and water is highly exothermic. During this reaction hydrogen gas is produces which catches fire due to heat released during reaction. Sodum is a very-very reactive metal.