These metals are called alkali metals because they form alkalies( i.e. strong bases capable of neutralizing acids) when they react with water.
Lithium(Li):
Lithium is part of the alkali metal group and can be found in the first group of the periodic table right below hydrogen. Like all alkali metals it has a single valence electron that it readily gives up to form a cation or compound.
Physical properties:
At room temperature lithium is a soft metal.
It is silver in color.
It is the least dense of the solid elements and is the lightest of all the metals.
It has the highest specific heat capacity of any solid element.
It burs with red flame.
Chemical properties:
Lithium is very reactive and flammable. It needs to be stored in mineral oil as it will react with air or water. It can cause burns if it comes into contact with the skin.
It's single valence electron allows it to be a good conductor of electricity.
It is flammable and can even explode when exposed to air and water. However, it is less reactive and explosive than the other alkali metals.
Occurrence:
Lithium is very reactive element so it is not found in its pure form in nature. It exist as mixture of stable forms. However, it is found throughout the world in a variety of areas including seawater, mineral springs, and igneous rocks.
The world's largest producer of Lithium is the United States. Another producers are Australia, Russia, Canada and china.
Uses:
Lithium is Mostly Used in lithium batteries.
It is Useful in the manufacture of ceramics and glass.
It is Useful in lubricating greases and in high performance aircraft materials.
it is a component of anti-depression drugs.
Discovery:
Lithium was first detected as an element by Swedish chemist Johann August Arfvedson in 1817 when he was analyzing petalite ore. Lithium comes from the Greek word "lithos" meaning "stone" or "rock". It was first isolated in its pure form by English chemist William Thomas Brande and Sir Humphrey Davy through the electrolysis of Lithium oxide.
Fascinating Facts :
It is very soft metal enough to cut with a knife.
It is so light it can float on water.
Lithium fires are difficult to put out. You can't use water as water will react with the lithium and could make the fire worse. A powder fire extinguisher is needed.
As it is the lightest metal, it can be alloyed with other metals such as aluminum and copper to make strong lightweight metals.
Lithium hydroxide can be used to purify air and remove carbon dioxide in spacecraft and submarines.
Sodium(Na):
Sodium is an alkali metal located in the first group of the periodic table. The sodium atom has 11 electrons and 11 protons with one valence electron in the outer shell which makes it highly reactive element.
Physical properties:
It is a very soft metal that can be easily cut with a knife.
It is silvery-white in color.
It burns with a yellow flame.
Chemical Properties:
Sodium is more reactive than Lithium.
It needs to store under Kerosene to avoid contact with air.
It has low density than water hence floats on water, but it reacts with water to form sodium hydroxide and hydrogen gas.
Its most of the compounds are water soluble.
Occurrence:
Sodium is highly reactive element so it is unstable in its pure form, it always exist as a compound in nature the most common is table salt (NaCl). It is largely found in seawater and in solid deposits.
Uses:
Table salt which is a compound of sodium and chlorine is mainly used for adding flavor to food but it is essential for survival of all living beings.
Sodium bicarbonate is used as baking soda to bake many food items like cake, biscuits and breads.
Sodium hydroxide is mainly used for making soaps.
Liquid sodium has been used as a coolant for nuclear reactors.
Sodium vapor is used in streetlights and produces a brilliant yellow light.
Discovery:
Sir Humphry Davy, a british chemist has discovered sodium in 1807. He isolated sodium from caustic soda by electrolysis and hence it got name from the English word soda. The symbol 'Na' comes from the Latin word "Natrium" meaning sodium carbonate.
Fascinating facts:
Sodium is the most important out of all alkali metals from commercial point of view.
it reacts quickly with water and also with ice to form sodium hydroxide and hydrogen.
It helps to maintain the proper fluid balance in the body's cells and also helps us to digest our food.
Our bodies lose sodium when we sweat. However, most people eat far more sodium than their bodies actually need. If the body runs low on sodium, it can cause the muscles to cramp.
Sodium is considered non-toxic, but too much of it can cause high blood pressure.
Potassium(K):
Potassium is the fourth element in the first group of the periodic table. Potassium atom have 19 electrons and 19 protons with one valence electron in the outer shell. Potassium is considered chemically similar to sodium, the alkali metal above it on the periodic table. It is very soft and can cut with a knife with little force.
Physical properties:
It is very soft silver metal.
It is less dense than water hence can float on water.
it burns with pale purple flame.
Chemical properties:
potassium is a very active metal. It reacts violently when coming into contact with water, producing heat and hydrogen gas. hence it is generally stored under oil or grease.
It also reacts with many other elements and substances such as oxygen, acids, sulfur, fluorine, and nitrogen.
Occurrence:
potassium reacts so readily with water, it is not found in its elemental form in nature. hence it is found in various minerals such as sylvite, carnallite, langbeinite, and kainite. Most minerals that contain potassium are referred to as potash. It can also be found in ocean water.
Uses:
It is a mineral plays many important roles in the body. fruits, cereals, milk etc. are good source of minerals.
It is useful to control high blood pressure and strokes.
Potassium chloride is used to make fertilizers.
In industries it is used in manufacturing of soaps, detergent,dyes, gunpowder and batteries.
Discovery:
Sir Humphry Davy, a british chemist has discovered Potassium in 1807. He isolated potassium from potash by electrolysis and hence it got name from the English word potash. The symbol 'K' comes from the Latin word "Kalium" meaning potash.
Fascinating facts:
Potassium bicarbonate is the chemical name for baking soda. It is used in fire extinguishers, baking powders, and antacids.
Some good sources of potassium in our diet include bananas, avocados, nuts, chocolate, parsley, and cereals.
Potassium chloride (KCl) is sometimes used as a substitute for table salt
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