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Table I. Bath Composition Zinc Metal1 Acid Chloride Zinc: All ammonium chloride Low ammonium potassium chloride Nonammonium or all-potassium chloride Alkaline Non-cyanide Zinc: Low chemistry High chemistry Cyanide Zinc: Low cyanide Mid cyanide High cyanide Zinc metal source: 0.8–1.2 1.8–3.0 1.0–1.5 1.8–2.5 3.5–4.5 10.0–14.0 16.0–20.0 10.0–12.0 10.0–12.0 10.0–12.0 All figures in oz/gal. Conversion to metric: oz/gal 7.49 = g/L 1 Acid chloride zinc—zinc chloride. Alkaline non-cyanide zinc—zinc oxide (preferably nonleaded). Cyanide zinc—zinc oxide or zinc cyanide. 2Sodium hydroxide source: mercury cell grade or rayon grade. 3Ammonium and potassium chloride source: untreated is preferred. 4Boric acid source: granular preferred, as powdered form creates a dusting problem. 1.5–2.5 3.5–6.0 11.0–14.0 2.0–4.0 3.0–5.0 4.0–6.0 16.0–20.0 25.0–30.0 3.0–5.0 5.0–6.0 5.0–5.5 2.0–4.0 Sodium Hydroxide2 Sodium Cyanide Ammonium Chloride3 16.0–20.0 Potassium Chloride4 Boric Acidd pH 5.0–6.0 270