Hydrogen is the lightest element in the periodic table. It consists of a single proton and one electron. Hydrogen is abundant in the universe and makes up about 75% of all matter.
Hydrogen is an important fuel for stars and plays a role in the nuclear fusion that powers them. Hydrogen is also used in industry as a chemical feedstock, and has potential applications as a clean energy source.
The word “hydrogen” comes from the Greek words “hydro” and “genes,” which mean “water” and “birth,” respectively. The name was coined by English chemist John Dalton in 1808.
Dalton hypothesized that all matter was composed of atoms, which he defined as indivisible units of matter with specific properties. He also proposed that atoms could combine to form molecules, which would account for the observed physical and chemical properties of substances. Dalton’s model was able to explain many observations at the time, but it did not explain why some atoms combined together while others did not.
In 1865, Lord Kelvin proposed that atoms were held together by an attractive force between their positive cores (protons) and negative electrons orbiting around them. This model explained why some atoms combined while others did not: those with more protons than electrons were attracted to those with more electrons than protons. The force between two hydrogen atoms was later determined to be the electrostatic force between their protons (positive charges) and electrons (negative charges). The strong electrostatic attraction between hydrogen’s positively charged nucleus (proton) and negatively charged electron creates a stable bond, making hydrogen one of the most abundant elements in the universe.