Question

State the property of metal used in the following:

Use of metal	Property
Zinc in galvanization
Aluminum in thermite welding

Answer 1

Galvanization:

• Galvanization is the process of placing a layer of zinc over the iron or steel objects which acts as a protective layering in turn prevents the corrosion of the metal objects.
• Zinc is used in the process of galvanization as it forms a covering layer of the metal objects such as iron. Zinc has the property of being less corrosive.

Thermite welding:

• Thermite welding is the process by which two metals are joined together by pouring a hot metal mixture of aluminum and iron oxide.
• Formula of Thermite: ${\mathrm{Fe}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+2\mathrm{Al}\left(\mathrm{s}\right)\to 2\mathrm{Fe}\left(\mathrm{s}\right)+{\mathrm{Al}}_2{\mathrm{O}}_3\left(\mathrm{s}\right)+\mathrm{Heat}$
• Aluminum is used as an oxidizing agent which has the ability to oxidize iron and produces a large amount of heat.

Use of metal	Property
Zinc is used in the galvanization	Forms a thick layer over iron objects
Aluminum in thermite welding	Has the ability to oxidize iron