2.7.1.136 KCl - 661781 2.7.1.136 Mg2+ - 661781 2.7.1.136 Mg2+ essential 640837, 640838, 640839, 640840 2.7.1.136 Mg2+ required 762485 2.7.1.136 additional information potassium chloride enhances reactivity, it is added in the reaction mixture at 0.06 M 640837, 640839, 640845