111. Solving a chemistry problem

As a result of paper chromatography of the analyzed solution containing a mixture of two ions X2 and Z2, using a mixture of collidine-water as a PF and a solution containing Sr2 cations as a standard, we obtained: L=100mm, l(X2)=52mm, l (Z2)=65mm; l(Sr2)=40mm. Calculate the values of the relative mobility coefficients for the cations X2 and Z2 and establish their nature, if it is known that for these conditions: Rs(Ba2 )=0.25; Rs(Ca2)=1.31; Rs(Mg2)=1.62.