discovery of hydrogen

Sources and Discovery of Hydrogen - Hydrogen is the lightest substance known and the most abundant element in the universe. It has a mass of just 0.09 g per litre at normal temperature and pressure. Though it is present in abundance in celestial bodies, like the sun an..

Hydrogen is the lightest substance known and the most abundant element in the universe. It has a mass of just 0.09 g per litre at normal temperature and pressure. Though it is present in abundance in celestial bodies, like the sun and stars, it is not present in a free state in our ..

The Swedish chemist Carl Wilhelm Scheele first prepared chlorine in 1770 by treating hot concentrated hydrochloric acid with manganese dioxide. Unfortunately, he thought that it was an oxygen containing compound and did not recognize it as an element. After more than 30 years, the English ..

Discovery of Ammonia - Joseph Priestley first prepared ammonia in 1775 by heating Sal ammoniac (ammonium chloride) with slaked lime. Due to its basic nature, he called it alkaline air. In 1785, Comte Claude-Louis Berthollet determined the chemical composition of ammonia (Fig.6.1..

The history of the discovery of cells dates back to the 17 t h century and is closely associated with the history of the invention of microscopes. An Italian microscopist Marcello Malpighi studied the structure of some plants and proposed the idea that plants are composed of tin..

Two scientists, Carl Scheele of Sweden and Joseph Priestly of England working independently, discovered oxygen. They published their discovery in 1777. Scheele obtained oxygen by heating potassium nitrate and mercuric oxide and called it "Fire Air". Priestley called it "Dephlogisticated ..

Joseph Priestley first prepared ammonia in 1775 by heating Sal ammoniac (ammonium chloride) with slaked lime. Due to its basic nature, he called it alkaline air. In 1785, Comte Claude-Louis Berthollet determined the chemical composition of ammonia (Fig.6.1..

. Thus the relative mass of such a particle = 1 amu and the absolute mass = 1.6 x 10 - 2 4 g. Because of their electrical neutrality, these particles were called neutrons We are now in a position of explain why the atomic mass of carbon is 12. It is now known that the carbon atom contains..

The credit of discovery of first noble gas argon goes to Henry Cavendish who performed number of experiments to study the composition of air. He found that air is approximately 79 per cent nitrogen and 21 per cent oxygen by volume. Traces of carbon dioxide and water vapor were thought to..