any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter

a fluid in the gaseous state having neither independent shape nor volume and being able to expand indefinitely

binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solvent

an inorganic compound with the formula H2Se.

a chemical compound with the formula BiH3.

any binary compound of boron and hydrogen.

(inorganic chemistry) any ionic derivative of ammonia in which a hydrogen atom has been replaced with a metal cation.

a radioactive isotope of hydrogen; atoms of tritium have three times the mass of ordinary hydrogen atoms

binary compound that occurs at room temperature as a clear colorless odorless tasteless liquid; freezes into ice below 0 degrees centigrade and boils above 100 degrees centigrade; widely used as a solvent

an inorganic compound with the chemical formula (BH)3(NH)3.

an inorganic compound with the formula H2Se.

a chemical compound with the formula BiH3.

any binary compound of boron and hydrogen.