i) Diborane - (c) Banana bonds

The formation of diborane leads to the creation of new types of bonding with hydrogen atoms a) 4 terminal – 2 centered – 2 electrons and b) 2 bridging – 3 centered – 2 electrons, leading to the formation of banana bonds. In other words, in total there are 12 valence electrons, (3 from each Boron and 6 from 6 6 H-atoms), now, out of these 4 H-atoms bind covalently with the 2 Boron atoms (8 used), while the remaining 4 electrons are shared by 2 Hydrogen – Boron atoms, form B-H-B bridge. This bridging is referred to as Banana bond.

(ii) Gallium - (d) Low melting, high boiling, useful for measuring high temperatures

Due to greater cohesive forces which held the structure together, Gallium exhibits high boiling point while its melting point is low. Therefore, used to measure high temperatures.

(iii) Borax - (a) Used as a flux for soldering metals

Borax is used for soldering metals. Borax is used

along with (flux) for welding purposes. Sometimes, it is also

mixed with water to solder jewellery and gold.As, it lowers the

melting pointand allows themolten mixture to flow easily in the

shapes. Thus, helps used in soldering.

(iv) Aluminosilicate - (e) Used as catalyst in petrochemical industries

Aluminosilicate is a compound which is composed of Aluminium and Silicon mainly, also called as Zeolites. Nowadays, aluminosilicates are commonly used in petrochemical industries as a catalyst used to synthesis ethylene and propene. These are the compounds which can accelerates the chemical reactions, called as catalysts. They are usually used in the preparation of gasoline from crude oil and in the petrochemical industries for cracking of hydrocarbons.

(v) Quartz - (b) Crystalline form of silica

Quartz is composed up of elements - Si and Oxygen and having formula . It is a crystalline structure formed by the joining of repeating units of. It is available in several colorsand varieties. They used in jewellery making and stone carving.

(a part showing crystalline form of Quartz)