Uses of Metals
- Metals are good conductors of heat & electricity and are malleable and ductile.
- Gold and silver are most malleable and best ductile metals.
- Silver is the best conductor of heat followed by copper.
- Aluminium and copper are good conductors of heat that’s why cooking utensils are made of them.
- Mercury offers high resistance to the flow of electric current.
- Sodium and potassium are so soft that they can be easily cut with knife.
- Metals are electropositive in nature.
- Almost all the metal oxide are basic in nature but zinc oxide and aluminium oxide are amphoteric.
Alkali metals and their compounds
- Metals of first group are alkali metals.
- This group lies in the s-block of the periodic table of elements as all alkali metals have their outermost electron in an s-orbital.
- Lithium, sodium, potassium, rubidium and cesium are alkali metals.
- These metals are stored under kerosene or liquid paraffin’s to protect them from action of air.
Sodium chloride (NaCl):
- Commonly known as table salt
- Used in the manufacturing of sodium hydroxide and chlorine gas.
- It is used as a starting material in the manufacturing of caustic soda.
- It is used in the removing of ice from road, now a- days CaCl2 and MgCl2 are also used for this purpose.
Sodium hydroxide (NaOH):
- Used in the refining of bauxite material.
- Used in soap, dyes and artificial industries.
Sodium bicarbonate (NaHCO3):
- It is commonly known as baking soda.
- Used for wool washing.
- Used in the fire extinguisher.
Sodium carbonate (Na2CO3)
- It is commonly known as washing soda.
- Used for softening of hard water.
- Mixture of sodium carbonate and potassium carbonate is known as Fusion mixture.
- It is commonly known as Glauber’s salt.
- It is used as purgative.
- It is commonly known as Hypo and used in the photography as fixing agent.
- It is known as pearl ash.
- Commonly known as caustic potash.
- Use in the preparation of soft soap.
- Its aqueous solution is known as potash Iye.
- Used in space capsules, submarines and breathing mask as it removes in carbon dioxide and carbon monoixide.
Alkaline Earth Metals and their compoundsThe alkaline earth metals are six elements in column (group) 2 of the Periodic table.
They are beryllium (Be),magnesium(Mg),calcium (Ca), strontium (Sr),barium (Ba), and radium (Ra).They have very similar properties: they are all shiny, silvery-white, somewhat reactive metal at same temperature and pressure.
- Mg(OH2) is known as milk of magnesia and use as an antacid.
- It is also known as quick lime.
- Used in the manufacturing of calcium chloride, cement and bleaching powder.
Calcium sulphate (CaSO4):The compound exists in three levels of hydration:
- anhydrous state (mineral name: "anhydrite") with the formula CaSO4
- dihydrate (mineral name: "gypsum") with the formula CaSO4(H2O)2.
- hemihydrate with the formula CaSO4(H2O)0.5
- It loses a part of water to form plaster of Paris.
- Plaster of Paris is a white powder which becomes hard on contact with water and is used in the manufacturing of statues.
Some Important Metals & Their Uses
- Ore of aluminium is bauxite.
- It is the third most abundant element in the earth’s crust.
- Used in the manufacturing of cooking utensils.
- Ammonal , a mixture of aluminium powder and ammonium nitrate is used as an explosive.
- The ore of tin is Cassiterite.
- The process of converting white tin to grey tin is known as tin disease or tin plague.
- Used in plating of iron to protect the iron from rusting.
- Tin amalgam is used in the manufacturing of mirrors.
- Main ore of lead is galena.
- Use in the preparation of sulphuric acid through chamber process.
- Lead acetate is known as sugar of lead.
- It is used in the galvanisation process to prevent the rusting of iron.
- Zinc sulphide is used in the preparation of X-ray screens.
- Zinc oxide is known as philosopher wool.
- It is the only metal which is liquid at room temperature.
- It forms alloys with all other metal except iron and platinum.
- Silvery white soft metal.
- Used as anode in Edison batteries.
- Extracted from the haematite ore and do not occur in Free State due to its reactivity.
- Ferric chloride is used as stypic to stop bleeding from the cut.
- Ferrous sulphate is used in making blue black ink.
- It is an alloy of iron, chromium and nickel.
- Used in making automobiles parts and utensils