The purpose of this work is to theoretically examine the diffusion of neutral alkali atoms in a neutral gas of atomic hydrogen, as well as their low-temperature elastic scattering properties. More specifically, the investigation tries to determine the temperature-dependent diffusion coefficient \(D(T)\) and the scattering length \(a\) and effective range \(r_{\mathrm {e}}\) of alkali-metal atoms in hydrogen. The computations are carried out quantum mechanically by considering the full interaction potentials for all alkali hydrides.