An empirical correlation between superconducting energy gaps 2△0 and the Hall coefficients RH of amorphous state and between superconducting energy gaps 2△0 of amorphous state and the Hall coefficients RHL of corresponding liquid metals is found respectively, that is: in numerous non-transition metals and alloys, 2△0 takes a maximum value as RH (or RHL)=-3.5--4.0×10-11m3/AS.