Hydrogen: the essentials Note that while hydrogen is normally
shown at the top of the Group 1 elements in the periodic table,
the term "alkaline metal" refers to the Group 1 elements from
lithium downwards and not hydrogen. Hydrogen is the lightest
element. It is by far the most abundant element in the universe
and makes up about about 90% of the universe by weight. It is
also the most abundant element in the earth's sun. Hydrogen as
water (H2O) is absolutely essential to life and it is present in
all organic compounds. Hydrogen is the lightest gas. Hydrogen
gas was used in lighter-than-air balloons for transport but is
far too dangerous because of the fire risk (Hindenburg). It
burns in air to form only water as waste product and if hydrogen
could be made on sufficient scale from other than fossil fuels
then there might be a possibility of a hydrogen economy.
Hydrogen: historical information Robert Boyle (1627-1691;
English chemist and physicist) published a paper ("New
experiments touching the relation betw