One would expect a proton to have a very large:

Which of the following chemicals contains chlorine?

Fill in the blanks:
$(1)$ In the crystal structure of ice, the oxygen atom is at a distance of $276 \ pm$ from four hydrogen atoms.
$(2)$ The relative proportion of tritium to protium is $1: 10^{18}$.

What is the nature of the nuclear spin in para-hydrogen?

Hydrogen generally forms covalent compounds. Give reason.

Which of the following statements is not true for hydrogen:
$1)$ It exists as a diatomic molecule.
$2)$ It has one electron in the outermost shell.
$3)$ It can lose an electron to form a cation which can freely exist.
$4)$ It cannot form ionic compounds.