What Are the Chemical Properties of Aluminium Including Reactions with Oxygen Water Acids and Bases
A prominent "group 13" element, which is also a member of the Boron family whose electronic configuration is 1s2 2s2 2p6 3s2 3p1 is known as Aluminium. The addition of the first three Ionization enthalpies of the Aluminium, AI3+ ions can form. It usually furnishes +3 oxidation states and also is a high electropositive element which is in the case of Aluminium Oxide (Al2O3). The other type of oxidation states is +2 and +1. A transparent Aluminium oxide (Al2O3) layer protects it which forms in the air. There are physical and chemical properties of Aluminium, and its uses can also be seen.
Three Properties Of Aluminium
To explain what are the properties of Aluminium, the 3 properties of Aluminium can be described as follows:
The first of the three chemical properties of Aluminium is the Reaction of Aluminium with air. Aluminium metal generally does not react with air as the surface of it is covered with an oxide layer which protects the coating from the attack of air. If the oxide layer gets damaged, the exposure of the Aluminium metal can be seen which reacts with oxygen and helps in the formation of amphoteric oxide (Aluminium (III) Oxide), Al2O3.
4Al (s) + 3O2 (l) → 2Al2O3 (s)
The second of the three chemical properties of Aluminium is the reaction of Aluminium with acids. Mineral acids react with Aluminium to make solutions which contain liquid AI (III) ion along with the release of hydrogen gas, H2. The reaction of Aluminium with HCl releases hydrogen gas.
2Al3+ (aq) +6HCl (aq) → 3H2 (g) + 6Cl– (aq)
This is how the reaction of Aluminium with hydrochloric acid happens.
The third of the three chemical properties of Aluminium is the reaction of Aluminium with alkalis. This reaction leads to the liberation of hydrogen gas (H2). Oxygen and Aluminium electronegativity make it possible for the Aluminium to form covalent bonds along with oxygen if Aluminium reacts with warm, sodium hydroxide solution to create a colourless solution of sodium tetrahydroxoaluminate along with the release of hydrogen gas.
2Na+ (aq) + 2[Al (OH)4]– + 3H2 (g) → 2Al (s) + 2NaOH (aq) + 6H2O
Other than the three properties of Aluminium which are chemical properties of Aluminium, there are few physical properties of Aluminium.
The 3 properties of Aluminium Which are Physical Properties, Can Be Explained:
Aluminium is a silver type of metal with a tint that is bluish.
The melting point is 660°C (1,220°F), and the boiling point is 2,327-2,450°C (4,221-4,442°F).
The density of Aluminium is 2.708 grams per cubic centimetre which is both malleable as well as ductile.
Uses Of Aluminium
Aluminium is utilized in a tremendous assortment of items including jars, foils, kitchen utensils, window outlines, lager barrels and plane parts. This is a result of its specific properties. It has a low thickness, is non-toxic, has high thermal conductivity, has incredible corrosion obstruction and can be easily cast, machined and shaped.
It is regularly utilized as alloy since Aluminium itself isn't stable. Compounds with copper, manganese, magnesium and silicon are lightweight however stable. They are significant in the development of planes and different types of transport.
The Biological Role Of Aluminium
Other than the three properties of Aluminium which are chemical properties of Aluminium as well as physical properties of Aluminium, no such biological role can be seen. +3 soluble in the plant makes it toxic. Acidic soils are due to the reaction of Aluminium with HCl found mostly on the Earth with AI3+ release from their minerals which the crops absorb.
Solved Example
1. What happens when there is a reaction of Aluminium with HCl?
The reaction of Aluminium with hydrochloric acid produces liquid aluminium chloride, AlCl3, as well as hydrogen gas, H2.
The chemical equation which is balanced explains this single replacement reaction that is
2Al(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2(g)↑
Remember that this reaction of Aluminium with hydrochloric acid will not happen when we add the piece of Aluminium to the hydrochloric acid solution. This is because the piece of Aluminium is covered by a layer of aluminium oxide, Al2O3, which protects Aluminium reacting with the water. The hydrochloric acid will need some time to work through this layer, but once it happens, the reaction will proceed faster, i.e. bubbling can be seen in the hydrochloric acid.
Fun Fact
In more than 270 minerals, Aluminium mostly can be found.
It is one of the most abundant minerals on Earth after oxygen and also silicon.
Aluminium as a global scale is one of the most used metals which do not contain iron.
Aluminium reflects almost 98% of infrared rays and 92% visible light.
Currently, Australia can be said as the largest producer of Aluminium.
FAQs on Chemical Properties of Aluminium and Its Reactivity
1. What are the chemical properties of aluminium?
The chemical properties of aluminium include its reactivity with oxygen, acids, bases, and halogens, and its amphoteric nature.
- It reacts with oxygen to form a protective layer of Al2O3.
- It reacts with dilute acids to produce aluminium salts and hydrogen gas.
- It reacts with strong bases to form aluminates.
- It forms ionic compounds such as aluminium chloride (AlCl3).
2. Why does aluminium not corrode easily?
Aluminium does not corrode easily because it forms a thin, protective oxide layer of Al2O3 on its surface.
- When exposed to air, aluminium reacts with oxygen: 4Al(s) + 3O2(g) → 2Al2O3(s).
- This oxide layer is dense and adherent.
- It prevents further contact between the metal and air or moisture.
3. How does aluminium react with oxygen?
Aluminium reacts rapidly with oxygen to form aluminium oxide, Al2O3.
- The balanced reaction is: 4Al(s) + 3O2(g) → 2Al2O3(s).
- The reaction forms a white, protective oxide coating.
- In powdered form, aluminium burns with a bright white flame.
4. How does aluminium react with acids?
Aluminium reacts with dilute acids to form aluminium salts and hydrogen gas.
- With hydrochloric acid: 2Al(s) + 6HCl(aq) → 2AlCl3(aq) + 3H2(g).
- With dilute sulphuric acid: 2Al(s) + 3H2SO4(aq) → Al2(SO4)3(aq) + 3H2(g).
5. How does aluminium react with bases?
Aluminium reacts with strong bases like sodium hydroxide to form sodium aluminate and hydrogen gas.
- The balanced reaction is: 2Al(s) + 2NaOH(aq) + 2H2O(l) → 2NaAlO2(aq) + 3H2(g).
- This reaction shows that aluminium is amphoteric.
- It dissolves in alkali despite being a metal.
6. What does it mean that aluminium is amphoteric?
Aluminium is amphoteric, meaning it reacts with both acids and bases.
- With acids, it forms aluminium salts and hydrogen gas.
- With bases, it forms aluminates such as NaAlO2.
- Its oxide, Al2O3, also reacts with both acids and bases.
7. How does aluminium react with water?
Aluminium does not react with cold water due to its protective oxide layer but reacts with steam to form aluminium oxide and hydrogen.
- With steam: 2Al(s) + 3H2O(g) → Al2O3(s) + 3H2(g).
- No reaction occurs with cold water under normal conditions.
- The oxide coating prevents further reaction.
8. How does aluminium react with halogens?
Aluminium reacts with halogens to form aluminium halides such as AlCl3.
- With chlorine: 2Al(s) + 3Cl2(g) → 2AlCl3(s).
- With bromine: 2Al(s) + 3Br2(l) → 2AlBr3(s).
- These reactions are vigorous and exothermic.
9. What is the oxidation state of aluminium in its compounds?
The oxidation state of aluminium in most of its compounds is +3.
- In Al2O3, aluminium is +3.
- In AlCl3, aluminium is +3.
- Aluminium loses three electrons to form Al3+ ions.
10. Why is aluminium considered a good reducing agent?
Aluminium is a good reducing agent because it readily loses three electrons to form Al3+ ions.
- It has a strong affinity for oxygen.
- In the thermite reaction: 2Al(s) + Fe2O3(s) → Al2O3(s) + 2Fe(l).
- Aluminium reduces iron(III) oxide to molten iron.
