Periodic table

By Christian paredez

Hydrogen

• Hydrogen is the lightest element• Hydrogen as water (H2O) is absolutely

essential to life and it is present in all organic compounds.

• Hydrogen is the lightest gas.• Hydrogen was discovered by Henry Cavendish

at 1766 in London.

Helium

• Helium is one of the so-called noble gases• Helium gas is an unreactive, colorless, and

odorless monoatomic gas. • Helium is the second most abundant element

in the universe.• Helium was discovered by Sir William Ramsay.

Lithium

• Lithium is a solid.• A freshly cut chunk of lithium is silvery• It is the first element within the second

period.• Lithium was discovered by Johan August

Arfvedson at 1817 in Stockholm, Sweden.

Beryllium

• Beryllium is a Group 2 (IIA) element.• Beryllium resists oxidation in air.• Beryllium compounds are very toxic.• Beryllium was discovered by Nicholas Louis

Vauquelin.

Boron

• It is a semiconductor rather than a metallic conductor.

• Chemically it is closer to silicon than to aluminum, gallium, indium, and thallium.

• Crystalline boron is inert chemically and is resistant to attack by boiling HF or HCl.

• Boron was discovered by Sir Humphrey Davy.

Carbon• It is found in abundance in the sun, stars, comets, and

atmospheres of most planets.• Carbon is found free in nature in three allotropic forms.• Graphite is one of the softest known materials while

diamond is one of the hardest.• Carbon was discovered by Known since ancient times

Nitrogen

• Nitrogen is a Group 15 element.• Nitrogen makes up about 78% of the

atmosphere.• However, its compounds are vital components

of foods, fertilizers, and explosives.• Nitrogen was discovered by Daniel Rutherford

in 1772.

Oxygen

• Oxygen is a Group 16 element.• Mars contains only about 0.15% oxygen.

• Oxygen is the third most abundant element found in the sun.

• Leonardo da Vinci suggested that air consists of at least two different gases.

Fluorine

• Fluorine is the most electronegative and reactive of all elements.

• It is a pale yellow, corrosive gas, which reacts with practically all organic and inorganic substances.

• Finely divided metals, glass, ceramics, carbon, and even water burn in fluorine with a bright flame.

• Fluorine was discovered by Henri Moissan at 1886 in France.

Neon

• Neon is a very inert element. • Neon forms an unstable hydrate. • In a vacuum discharge tube, neon glows

reddish orange.• Neon was discovered by Sir William Ramsay

Sodium

• Sodium is a Group 1 element.• The chemistry of sodium is dominated by the

+1 ion Na+.• Sodium salts impart a characteristic

orange/yellow color to flames and orange street lighting is orange because of the presence of sodium in the lamp.

• Sodium was discovered by Sir Humphrey Davy at 1807 in England.

Magnesium

• Magnesium is a grayish-white, fairly tough metal.

• Magnesium is the eighth most abundant element in the earth's crust.

• Magnesium metal burns with a very bright light.

• Black recognized magnesium as an element in 1755.

Aluminum

• Pure aluminum is a silvery-white metal with many desirable characteristics.

• It is somewhat decorative. It is easily formed, machined, and cast.

• Pure aluminum is soft and lacks strength.• The ancient Greeks and Romans used alum in

medicine as an astringent

Silicon

• Silicon is present in the sun and stars and is a principal component of a class of meteorites known as aerolites.

• Silicon makes up 25.7% of the earth's crust.• It is found largely as silicon oxides.• Jacob Berzelius is generally credited with the

discovery of silicon in 1824.

Phosphorus

• It is an essential component of living systems.• Found in nervous tissue, bones and cell

protoplasm. • Phosphorus exists in several allotropic forms

including white.• Phosphorus was discovered in 1669 by Hennig

Brand

Sulfur

• Sulfur is a pale yellow, odorless, brittle solid.• Which is insoluble in water. • It is a minor constituent of fats, body fluids,

and skeletal minerals.

Sulphur was known in ancient times and referred to in Genesis as brimstone

Argon

• Argon is a colorless and odorless gas• Argon is very inert (indeed it is referred to as

one of the noble gases) and is not known to form true chemical compounds.

• Argon was discovered by Lord Rayleigh and Sir William Ramsay in 1894.

Potassium

• Until the 18th century no distinction was made between potassium and sodium.

• potassium carbonate was mixed with animal fat to make soap.

• Potassium was discovered by Sir Humphrey Davy at 1807 in England.

Calcium

• Calcium as the element is a grey silvery metal. • The metal is rather hard.• Calcium was discovered by Sir Humphrey Davy

at 1808 in England.

scandium

• develops a slightly yellowish or pinkish cast upon exposure to air.

• Scandium is a silvery-white metal which• Scandium was discovered by Lars Fredrik

Nilson at 1879 in Sweden.

Titanium

• Titanium s a lustrous, white metal when pure.• Titanium minerals are quite common. • Titanium was discovered by the Reverend

William Gregory in 1791.

Vanadium

• Pure vanadium is a greyish silvery metal.• is soft and ductile.• Vanadium was discovered by Andres Manuel

del Rio and Nils Sefström at 1801 in Mexico.

Chromium

• Chromium is steel-gray, lustrous, hard, metallic.

• takes a high polish.• Chromium was discovered by Louis-Nicholas

Vauquelin at 1797 in France.

Manganese

• Manganese metal is gray-white.• is harder and very brittle.• Manganese was discovered by Johann Gahn at

1774 in Sweden.