Reactivity of Group 13 towards Water and Metals

The periodic table is composed of elements, and these elements are divided into groups. The electron configurations of elements can be used to divide them into groups. The valence electrons of these elements lie in s and p orbitals, which are filled. The valence electrons of the outer transition metals lie in d orbitals (groups 3-11 on the periodic table). The transition elements are the ones whose f orbitals are filled.

Group 13 Elements

The capacity of an element to shed its outer valence electrons gives them metallic properties, which results in strong thermal and electrical conductivity, among other physical and chemical properties. There are 20 radioactive metals in the 1, 2, 3, 12, 13, 14, and 15 groups of the table. A few radioactive elements are copernicium, flerovium, polonium, and livermorium. These elements are also metals. 

In addition to these elements, there are other elements called metalloids. A metalloid can have properties with a mix of metals and nonmetals. These are commonly semiconductors. The remaining elements in the table are nonmetals. Metals generally form cations and ionic compounds (having ionic bonds), whereas nonmetals produce anions or molecular compounds. But if they combine, they form salts. Salt is an ionic compound having both cations and anions.

Elements of group 13

The metalloid boron and metals like aluminium, thallium, indium, and gallium are elements of Group 13. Boron is the lightest element with qualities of semiconductors and forms covalent bonds rather than ionic ones. The other members are metals, but their oxides and hydroxides have different properties and reactivity. Aluminium and gallium oxides and hydroxides show both acidic and basic qualities. Amphoteric elements react with both acids and bases.

Amphoteric property in elements helps to possess qualities of both nonmetallic and metallic. Thallium and indium oxides and hydroxides show metallic properties. Gallium has an unusually low melting point (about 30 °C). It can even melt in your hand.

Aluminium in the group shows both these properties and reacts with both acids and bases. Thus, it is called amphoteric. The following is an example of an acid reaction:

2Al (s) + 6 HCl (aq) → 2AlCl3 (aq) + 3 H2 (g)

In a reaction, the products of aluminium with a base will depend upon the reaction conditions. For example: 

2 Al (s) + 2 NaOH (aq) +6 H2 O (l) → 2Na [Al(OH)4] (aq) + 3H2 (g) 

Reaction with aluminium will produce hydrogen gas in both acids and bases.

The valence shell electron configuration of this group is ns²np¹. When aluminium reacts, it takes all of its valence electrons, thus producing compounds with an oxidation state of 3+. For example, compounds such as AlF3 and Al2(SO4)3are covalent. 

Elements like thallium, indium, and gallium also form ionic compounds having M3+ ions. These three elements present an oxidation state of 3+ obtained from the three valence electrons. They also present the oxidation state sometimes (in this case, 1+), which is two less than the expected value.

If the stable ion is produced with an oxidation state two lower than expected for the group, it shows an inert pair effect. The elements with inert pair effect elements, the valence s orbital is a pair of electrons. The inert pair effect is lower for p-block elements in general. The Tl+(aq) ion is more stable in aqueous solutions than the Tl3+ ion (aq). These metals also react with water and air to produce 3+ ions. But thallium interacts to produce thallium(I) derivatives. Sulphur, phosphorus, and halogens are all metals of group 13. These elements directly react with nonmetals to produce compounds.

AlCl3+(C2H5)2O→Al(C2H5)2OCl3

Group 13 metals are mostly all reactive. The passivation process happens when a strong film of metal produces oxide when exposed to air. If passivation is disturbed, the metal will start reacting. You can disturb the passivated metal to mercury so that the film doesn’t form. 

A few metals dissolve in the mercury, forming an amalgam that removes the protective oxide layer, exposing the metal for reaction. This amalgam causes these elements to react with water and air.

Aluminium is an excellent reducing agent that can separate some metals from their oxides rather than other reducing agents. Aluminium is crucial for separating Mo, W, and Cr from their oxides, despite being more expensive than carbon reduction.

The reaction of group 13 with water

Water has a low reactivity towards Group 13 elements. Boron (B) does not react with water at all. The element that reacts with water is aluminium. It seems to react, but it forms an outer layer of aluminium oxide (Al²O³), which is a solid form and protects the rest of the metal.

2Al + 6H2O →2 Al (OH)3+ 3H2

Conclusion

This article tells you about the importance of reactivity of group 13 elements towards water and metals. Among all the elements, boron doesn’t react with water and steam, but if we increase the temperature, boron shows reactivity with steam. Boron also doesn’t show reactivity towards metals, which highlights its nonmetallic nature.