Question

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> What do the following symbols [or formula] denote : $\text{2H}$ ; ${\text{H}}_2$ ; ${\text{H}}^{+}$

Answer 1

<!--td {border: 1px solid #ccc;}br {mso-data-placement:same-cell;}--> $\text{2H}$ denotes — 2 atoms of hydrogen
${\text{H}}_2$ — a molecule of hydrogen
${\text{H}}^{+}$ — an ion