Hydrogen itself is an atom. If that hydrogen atom were to lose/gain/share electrons it would become an isotope/ ion
The gas formed when hydrogen atoms fuse is helium. Stars do this.
carbon atoms, hydrogen atoms, hydroxide atoms
Hydrogen is a molecule formed by three atoms out of which two are hydrogen and one is oxygen
an ionic compound is formed
A molecule of water is formed with a polar covalent bond.
A cation, which is a positively charged ion, is formed when an atom loses electrons.
Most of the hydrogen was formed during the Big Bang.
If atoms gain electrons, negatively charged anions are formed. If atoms lose electrons, positively charged cations are formed.
Covalent
Hydrogen
Yes, hydrogen and oxygen atoms form covalent bonds when they chemically combine.
When both -NH2 and -COOH replace hydrogen atoms on the same carbon atom, an amino acid is formed.