Calculate the relative molecular mass of H2S.
Atomic mass of hydrogen() = 1 a.m.u
Atomic mass of sulphur() = 32 a.m.u
Molecular mass of hydrogen sulphide() =2 x Molecular mass of Hydrogen() + Molecular mass of Sulphur()
= 2 x 1 + 32 = 34 a.m.u
Therefore, relative molecular mass of hydrogen sulphide () = 34 a.m.u.