Isotope of hydrogen

[Tommyb323]

which of these are not an isotope of hydrogen:

1H0
1H1
2H1
3H1

[dynamicduo]

Not clear from the question but if the first number and second number are above and below and both followed by H then the top number is the mass number (in simple terms = no. of protons + no. of neutrons) and the lower no. is the atomic number (ie the no. of protons) then the first is not an isotope of hydrogen but the other 3 are.
1H0 doesn't make sense as it has no protons and is not an element
1H1 is hydrogen with 1 proton and 0 neutrons
2H1 is deuterium (a hydrrogen isotope) with 1 proton and 1 neutron
3H1 is tritium (a hydrrogen isotope) with 1 proton and 2 neutrons