Experimental measurements have been carried out to determine the compositions of coexisting gas and liquid phases for binary mixtures of hydrogen with the following substances as the second component: nitrogen, carbon monoxide, argon, methane, ethylene, ethane and carbon dioxide. For most of these mixtures the entire region of gas-liquid equilibrium has been explored for the first time. This region is bounded in pressure-temperature space by the vapor-pressure curve of the heavy component, the gas-liquid critical line (where gas and liquid phases become identical) and the 3-phase region solid-liquid-gas. In all of the systems described here the latter two lines intersect to form a critical end point. The general qualitative features of these phase diagrams are described, and compared to those of helium mixtures studied earlier.