Pressure-composition isotherms for hydrogen absorption and desorption have been measured for several alloys of the LaNi5-xAlx family at 298, 308, 323, 333, and 348 K, and the DELTAH-degrees and DELTAS-degrees of the hydride formation reaction were obtained. The equilibrium pressure is strongly related to the aluminum content in the alloy. Other specific properties which have been determined are the density of the metal alloys and the particle size distribution and surface area of the material after about 50 absorption/desorption cycles with pure hydrogen. Additionally, the solubility and the diffusion coefficient of hydrogen in cyclohexane have been measured, and the solubility of hydrogen in ethanol has been correlated with results available in the literature.