Laser-ablated Sb and Bi atoms react with hydrogen during condensation in excess hydrogen, neon, and argon to form the SbH and BiH diatomic molecules. In addition the new Group 15 MH2 dihydride radicals and the MH3 trihydrides are observed for Sb and Bi metals. Although BiH3 is of limited stability in the gas phase, BiH3 is formed by further H atom reactions with BiH2 in solid hydrogen and neon. No evidence is found for the thermochemically unstable BiH5 molecule.