Joseph Gay-Lussac summary

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Below is the article summary. For the full article, see Joseph-Louis Gay-Lussac.

Joseph Gay-Lussac, (born Dec. 6, 1778, Saint-Léonard-de-Noblat, France—died May 9, 1850, Paris), French chemist and physicist. He showed that all gases expand by the same fraction of their volume for a given temperature increase; this led to the devising of a new temperature scale whose profound thermodynamic significance was later established by Lord Kelvin. Taking measurements from a balloon flying more than 20,000 ft (6,000 m) high, he concluded that Earth’s magnetic intensity and atmospheric composition were constant to that altitude. With Alexander von Humboldt, he determined the proportions of hydrogen and oxygen in water. He is remembered as a pioneer investigator of the behaviour of gases and techniques of chemical analysis and a founder of meteorology.

Sir Humphry Davy Summary

Sir Humphry Davy was an English chemist who discovered several chemical elements (including sodium and potassium) and compounds, invented the miner’s safety lamp, and became one of the greatest exponents of the scientific method. Davy was the elder son of middle-class parents who owned an estate in

potassium Summary

Potassium (K), chemical element of Group 1 (Ia) of the periodic table, the alkali metal group, indispensable for both plant and animal life. Potassium was the first metal to be isolated by electrolysis, by the English chemist Sir Humphry Davy, when he obtained the element (1807) by decomposing

iodine Summary

Iodine (I), chemical element, a member of the halogen elements, or Group 17 (Group VIIa) of the periodic table. atomic number 53 atomic weight 126.9044 melting point 113.5 °C (236 °F) boiling point 184 °C (363 °F) specific gravity 4.93 at 20 °C (68 °F) oxidation states −1, +1, +3, +5, +7 electron

sodium Summary

Sodium (Na), chemical element of the alkali metal group (Group 1 [Ia]) of the periodic table. Sodium is a very soft silvery-white metal. Sodium is the most common alkali metal and the sixth most abundant element on Earth, comprising 2.8 percent of Earth’s crust. It occurs abundantly in nature in