Q4 Calculate total alkalinity and indicate what fraction corresponds to hydroxides, carbonates and bicarbonates, of the following samples. A) A 100 mL sample of water is tested for alkalinity. The normality of the sulfuric acid used for titrating is 0.02 N. 0 mL is used to pH 8.3, and 7.6 mL titrant is used to pH 4.5. B) A water sample is tested for alkalinity. The phenolphthalein alkalinity is 10 mg/L as CaCO3 and the total alkalinity is 52 mg/L as CaCO3 for this water sample. [25 marks]

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