Various Mg-3(PO4)(2)/MgO systems containing different proportions of both components were synthesized. The solids were characterized in structural terms by X-ray diffraction, thermal gravimetric analysis, and diffuse reflectance infrared spectroscopy; also, their surface properties were determined from N-2 adsorption-desorption isotherms and their chemical properties were measured with various titrants. An increasing P content in the solids was found to result in decreasing specific surface area and basicity. The solids were used as catalysts for the transformation of 2-hexanol and the alkylation of aniline with methanol. Dehydrogenation selectivity in the former was found to be highly correlated with basicity of the solid; also, alkylation activity and selectivity toward N,N'-dimethylaniline in the latter were found to increase with increasing P content.