Chemistry - Surface Chemistry Question with Solution | TestHub

Given: $Au-sol,S{b}_2{S}_3-sol$

Methylene blue, $Ti{O}_2$ sol, Gelatin, Starch, Congo red, $F{e}_2{O}_3\cdot x{H}_{2}O$.

Number of common positive sols $x=$

Number of common negative sols $y=$

Then the $\frac{2x-y}{2}$ value is: