Table 2: Rate data for the effect of added cations (Ca2+ and Mg2+) on the rate of reaction of naphthol green B with at [ ] =  mol dm−3, [ ] =  mol dm−3, [H+] =  mol dm−3,  mol dm−3,  nm, and = °C.

Ion103[ion], mol dm−3103 , s−1 , dm3 mol−1 s−1

Ca2+1.08.251.47
10.07.841.40
20.07.301.30
60.07.051.26
80.06.911.23
200.05.570.99

Mg2+1.07.421.33
5.05.591.00
10.04.480.80
20.04.110.73
80.03.650.65
200.02.650.47