Metals are the some of the first discovered elements on the earth.
They have been used by man since even before early human civilization.
There are many uses of metals to man hence they are highly priced and form a valuable commodity.
They have become indispensable in man’s life and with advancement of technology, many metals are further
researched to make better products.
Facts About Metals
1. Many heavy metals are toxic to the body at doses above the body capacity to handle them. Hence poisoning due to heavy metals is a common issue in medical field as some of them are also used to cure diseases. This happens due to accidental over dosing or deliberate pollution from industrial waste into rivers and soil.
2. Some heavy metals like arsenic are also used as poisons to cause death by deliberate consumption.
3. Metals are the only elements in the periodic table which are available as objects in pure element form. The metals atoms are bound to each by metallic bonds and these atoms exist as lattice. When the lattice is disturbed due to removal of few atoms, there is chance that they could convert to monoatomic element form devoid of metal properties.
4. They are all extracted from earth by different extraction processes. The regions of earth with high amount of metal containing earth are called as mines.
5. All the metals are solids in nature at room temperature except the mercury which is in the liquid form.
6. When exposed to heat, metals expand due to vibrations of atoms within the lattice. When cooled they tend to contract due to loss of vibration energy.
7. They are good conductors of heat and electricity hence they are used in making cookware, furnaces and also electric wires.
8. Mixture of two or more metals is called an alloy. These alloys impart special properties to metals which sometimes can be very useful. Ex: Bronze is an alloy of copper, tin, aluminum, manganese, nickel, zinc.
9. All metal oxides are alkaline in nature. When mixed in water they form a solution with pH range above 7. Hence, they readily react with acids to form a neutralization reaction.
10. Most metals when left open in air get corroded due to oxidation. The exception is only metals like aluminum, gold, silver and platinum which undergo negligible oxidation.
Some metals undergo oxidation at faster rate while other are slow. But, this oxidation drains to mass of metals and leads to degeneration over time. For example copper undergoes faster oxidation in few minutes to hours. While, different forms of iron take months to years to get oxidized.
11. Some metals are hard to obtain in pure form. That is there are not extracted from an ore directly. They are obtained along with others during extraction. Example aluminum is the most abundant metal and it comprises of 8% of earths crust. However, it is mostly combined with 270 different minerals.
12. Some metals are highly reactive in pure form hence they require special storage techniques to avoid being damaged. Ex: Sodium metal is stored in kerosene or liquid paraffin.
13. Most metals are highly resistant to heating and require high temperature and prolonged exposure to mold them into desired shaped and structure.
14. Metals like aluminum, copper, silver, gold, show physical properties like lustrous (shiny), ductile (to form wires) yielding, opaque, high melting point, high density, brittleness etc.
15. Only few metals like sodium and potassium react with water to form hydroxides. In doing so they release a lot of heat energy as if it is explosive. Also sodium is the metals which burns when exposed to fire which is not seen in other metals.
16. Metals can be recycled from manufactured objects like electronics, furniture etc, by electrostatic separation, pyrolysis etc.
17. Heavy metals like iron once formed into an object can stand so for hundreds of years if well maintained.
18. Before discovery of papers, metals were also used as records to store poetry, history and other important issues in the past. They were preferred over leaves and other materials for writing as they were less susceptible to be damaged by fire accidents.
19. Metals are also part of living beings and help in their survival. Iron is present in hemoglobin which helps to transfer oxygen in the body. Sodium, magnesium, potassium, calcium are electrolytes and help in conduction of nerve impulses in nervous system. Metals like copper, zinc, manganese etc are present as part of enzymes and other biological substances in the body.