... ml 5 0-2 00 10 0-4 00 2 5-5 00 5 0-2 00 1 0-4 0 2 0-8 0 5-2 0 1 0-4 0 10 Reagents Use reagents low in iron Use iron-free distilled water in preparing standards and reagent solutions Store reagents in glass-stoppered ... synthetic sample containing Cl-, 241 mg l-1; Ca, 108 mg l-1; Mg, 82 mg l-1; NO3 N, 1.1 mg l-1; NO2 N, 0.25 mg l-1; K, 3.1 mg l-1; Na, 19.9 mg l-1; SO4 2-, 259 mg l-1 and 42.5 mg total alkalinity ... (HNO3) 1. 174 -1 .189 1.83 4-1 .836 1.40 9-1 .418 Percentage of active ingredient in concentrated acid 3 6- 37 9 6-9 8 69 -7 0 Molarity of concentrated acid (mol l ) 1 1-1 2 18 1 5-1 6 -1 Table 7. 2 Volume (ml) of...