Uses of Metals And Non-Metals

Metals are all around us. Examine the uses of some common metals such as aluminium, iron, copper, gold, silver, etc.

1.0Metals

Iron

As compared to other metals iron is widely used. Iron is used because it is malleable, ductile, hard and strong. The hardness and strength of iron are generally improved by the presence of small quantities of carbon (less than 1.5%) which turn the iron into steel.       

Iron or more precisely steel, is used for making objects as small as pins and nails to huge structures like bridges. Iron is also used for making engine parts, iron sheets and reinforced concrete (used in the construction industry).

Tin

White metal, hammered out into thin sheets.

Example: Tin foil

Used to: Metal coatings to prevent chemical action and corrosion, Preserve food, Panel lighting, Soldering.

Zinc

Bluish white metal forms alloys like brass, bronze.

Used to Galvanizing: The metal zinc is mainly used to prevent steel from rusting. Steel is coated with a thin layer of zinc or by electroplating, Anti-corrosion materials, Medicinal fields, Alloys - The important alloy - brass - has zinc as one of its components.

Lead

Soft bluish-grey colour heavy metal which melts at a low temperature. Hammered into any shape

Used to: Making water-pipes, utensils, Alloys, Batteries, Pigments

Aluminium

By virtue of its lightweight quality, aluminium is used in making overhead cables to carry power in high-voltage electric lines. It is used in making alloys such as duralumin, magnesium and alnico. Being light and strong, aluminium alloys are used to make bodies and engine parts of aircrafts and automobiles.

It is used for making cooking utensils. Aluminium foil is used to wrap food. Aluminium powder is used in paints.

Chromium

Chromium is used in the manufacture of stainless steel, which is an alloy of iron, carbon, chromium and nickel. It is used in electroplating. The shining parts of bicycles are chrome-plate. Nichrome, an alloy of chromium, iron and nickel is used in making 'heating elements' of electric heaters.

Copper

A very good conductor of electricity, it is widely used in electrical wires and cables. It is used for making components of electrical switches. Copper coils are used in electrical motors and transformers. Being a good conductor of heat, it is used to make bottoms of stainless steel vessels. Copper is alloyed with tin to make the alloy bronze and with zinc to make the alloy brass.

Gold and silver

The main uses of gold and silver are as follows: For making jewellery and decorative articles: Gold and silver are two of the most malleable and ductile metals known. This coupled with their shiny lustre and inert nature, makes them suitable for making jewellery and decorative articles.

In dentistry: Gold and silver are used as filling in dentistry. They are dissolved in the mercury to form an amalgam.

Gold and silver are used for making jewellery. 

Mercury

Mercury is a silvery white, liquid metal. It does not moisten glass and it expands a lot on heating. Therefore it is used in :

(i) Thermometers (as thermometric liquid).

(ii) Barometers and other scientific apparatus.

(iii)Dentistry, the filling into teeth cavities in the form of alloys known as silver amalgam and gold amalgam.

Platinum

Platinum is a lustrous and a very precious metal. It is not reactive, just as is gold, Platinum is an excellent catalyst. It is used :

(i) For making electrodes and electrolytic cells.

(ii) For making expensive ornaments and watches.

Magnesium (Mg)

It is available in the form of ribbons. It is used :

(i) In fireworks, because it burns with a dazzling light.

(ii) For making fuse wire and an alloy called magnalium.

(iii) We all enjoy fireworks at Diwali. The brilliant white light seen when fireworks are set off is due to powdered magnesium.

Noble metals

Some metals remain unaffected in air, water, acidic solution or alkaline solution and are found in free state. They are chemically unreactive. They are known as noble metals or inert metals - gold, silver and platinum are noble metals. They have a metallic luster for a long time.

2.0Non-Metals

Just like metals, a variety of non-metals find use in our day-to-day life in one form or the other. Let us discuss the uses of some non-metals one by one.

Oxygen and nitrogen

Oxygen and nitrogen have an important role in sustaining life. It was also mentioned that oxygen is important for steel production and that nitrogen is converted into fertilizers and explosives.

Carbon 

Carbon forms the backbone of many important biomolecules such as carbohydrates, proteins, and fats. Diamond, a naturally occurring form of carbon, is used as a gem in jewellery as it sparkles brilliantly. Diamond is the hardest substance. 

Because of its hardness, diamond is used for cutting glass and drilling hard rocks. The other crystalline form of carbon is graphite. Graphite is soft and its layers slip over one another. This makes graphite very useful as a lubricant particularly in machinery operating at high temperatures. Graphite marks on paper and can easily be written on it. It is therefore used in lead pencils. Graphite is a good conductor of electricity. Hence, it is used as an electrode.

Chlorine

(i) Water is made fit for drinking (potable water) by treating it with chlorine to kill harmful bacteria (this process is called sterilization). 

(ii) Chlorine is also used in the manufacture of chlorine - containing organic compounds. Probably the most widely used of these is the plastic polyvinyl chloride (PVC).

Iodine 

Iodine is a dark violet non-metallic compound. Iodine is required as a trace element in living organisms as a constituent of thyroid gland. Iodine dissolved in ethanol as tincture of iodine is used in medicine as a mild antiseptic.

(i) Like chlorine, iodine has germicidal properties (by ability to kill germs). A 2% solution of iodine in alcohol (tincture of iodine) is used as an antiseptic. 

(ii) Iodine is needed for making valuable organic compounds of value such as medicines. 

(iii) Iodine is an essential element for healthy growth. Lack of iodine in the diet results in the disease goitre.

Note : The process of adding very small amounts of fluorine salts to drinking water to prevent tooth decay is called fluoridation.

Boron 

(i) Boron rods are used as control rods in nuclear reactors. 

(ii) Boron filaments are used in making light composite materials for aircraft. 

(iii) Boric acid, an important compound of boron, is used in solution form as a mild antiseptic. 

(iv) Its compounds borax and boric acid are used in the manufacture of pyrex, the heat-resistant borosilicate glass. 

Silicon

(i) Very high-quality silicon is used for making semiconductors from which microchips are made. It is therefore the backbone of the electronic and computer industry. 

(ii) Its compound with carbon (SiC), known as carborundum, is used as an abrasive material.

computer microprocessor made of silicon 

Phosphorus 

(i) It is used for the manufacture of phosphatic fertilisers called superphosphates. 

(ii) It is used for the manufacture of orthophosphoric acid, which is a major industrial chemical. 

(iii) It is used in the manufacture of matchboxes – the coating on the side of matchboxes contains about 50% red phosphorus. 

Sulphur

(i) It is used in the manufacture of sulphuric acid, sulphur dioxide gas, sulphides and other sulphur-containing industrial chemicals. 

(ii) It is used as an insecticide and fungicide in agriculture. 

(iii) Due to its fungicidal properties, it is used in skin ointments. 

(iv) It is used for vulcanising rubber (making rubber harder). 

(v) It is used in making gun powder.

Noble gases 

(i) Helium is used in airships because it does not burn. It is also used to fill balloons that travel to great heights with the instruments giving the data on which weather forecasts are based. 

(ii) Neon is extensively used in street lighting and advertising signs. 

(iii) Argon is the preferred gas for the common gas-filled electric light bulbs. 

(iv) Xenon is used in high intensity lamps in the cinema and for the standard fading tests of textiles. 

(v) Another noble gas krypton is used in lasers, which produce very intense beams of light. Krypton lasers are used in eye surgery, to prevent bleeding on the retina. The laser is directed to the points where bleeding might occur. The intense light makes blood clot. Arc welding uses an electric arc to melt the metals being welded. It is often carried out in a 'blanket' of argon to stop oxygen reacting with the metals.

Hydrogen

It is used as a reducing agent.  It is used for converting vegetable oils into ghee. It is used for making fertilizers by ammonia.