A critical review of available data on the heats of chemisorption of gases at metals is given. The effect of upward technical
and procedural trends on measured results is demonstrated. The results for surfaces approached to their states occurring in
catalytic processes are accentuated. Several tens of chemisorbent/gas systems are considered; a number of the results are
confirmed by several independent measurements. The coverage-independence of heats of chemisorption for powders, supported
catalysts, components of multi-component catalysts, and films is demonstrated; the better the techniques and procedures, the
closer to zero the angle between the heat-coverage function and the abscissa. The principal conclusion on surface homogeneity
of stabilized surfaces is made.