Hydrogen was probably “discovered” many times. Many early chemists reported finding a “flammable gas” in some of their experiments. In 1671, for example, English chemist Robert Boyle (1627-91) described experiments in which he added iron to hydrochloric acid (HCl) and sulfuric acid (H 2 SO 4 ). In both cases, a gas that burned easily with a pale blue flame was produced.
The problem with these early discoveries was that chemists did not understand the nature of gases very well. They had not learned that there are many kinds of gases. They thought that all the “gases” they saw were some form of air with impurities in it.
Cavendish discovered hydrogen in experiments like those that Boyle performed. He added iron metal to different acids and found that a flammable gas was produced. But Cavendish thought the flammable gas came from the iron and not from the acid. Chemists later showed that iron is an element and does not contain hydrogen or anything else. Therefore, the hydrogen in Cavendish’s experiment came from the acid:
Hydrogen was named by French chemist Antoine-Laurent Lavoisier (1743-94). Lavoisier is sometimes called the father of modern chemistry because of his many contributions to the science. Lavoisier suggested the name hydrogen after the Greek word for “water former” (that which forms water). (See sidebar on Lavoisier in the oxygen entry in volume 2.)