who was the first to discover it?
Henry Cavendish was the first to recognize hydrogen gas, and Antoine Lavoisier gave the element the name hydrogen
Hydrogen
 In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "inflammable air". He speculated that "inflammable air" was in fact identical to the hypothetical substance called "phlogiston" and further finding in 1781 that the gas produces water when burned. He is usually given credit for the discovery of hydrogen as an element. In 1783, Antoine Lavoisier gave the element the name hydrogen (from the Greek ὑδρο- "hydro" meaning "water" and -γενής "genes" meaning "creator") when he and Laplace reproduced Cavendish's finding that water is produced when hydrogen is burned.
name of a row in the periodic table The seven rows of the table, called periods what is this table about? It is a tabular display of the chemical elements, which are arranged by atomic number, electron configuration, and recurring chemical properties can you name some chemical elements? Hydrogen, oganesson, plutonium what is the atomic number of the first element? Atomic numbers 1 can you name some things that react with this element? Chlorine and fluorine what are some of its isotopes? Deuterium, tritium, protium
wiki:7772610
Hydrogen [SEP] Discovery and use
In 1671, Robert Boyle discovered and described the reaction between iron filings and dilute acids, which results in the production of hydrogen gas. In 1766, Henry Cavendish was the first to recognize hydrogen gas as a discrete substance, by naming the gas from a metal-acid reaction "inflammable air". He speculated that "inflammable air" was in fact identical to the hypothetical substance called "phlogiston" and further finding in 1781 that the gas produces water when burned. He is usually given credit for the discovery of hydrogen as an element. In 1783, Antoine Lavoisier gave the element the name hydrogen (from the Greek ὑδρο- "hydro" meaning "water" and -γενής "genes" meaning "creator") when he and Laplace reproduced Cavendish's finding that water is produced when hydrogen is burned.