By Chrys Lin – Updated March 24, 2022
Hydrogen is the simplest chemical element and the first entry on the periodic table. It has no color, odor, or taste, and when it combusts in air it forms water.
Pinpointing the total amount of free hydrogen on Earth is challenging because its low density allows it to escape the planet’s gravity. Nevertheless, hydrogen is ubiquitous in Earth’s chemistry. It is a key component of water—the most abundant compound on our planet—and it is present in virtually every organic molecule. In fact, hydrogen atoms constitute roughly 61 % of the atoms that make up the human body.
Hydrogen holds promise as a future energy source. When it reacts or is electrolyzed, it can generate steam, electricity, or fuel for vehicles. The appeal of hydrogen lies in its clean profile: the sole by‑product of its combustion is water, which is harmless to the environment. However, its inherent instability and high flammability make handling and storage a significant technical challenge.
