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A supply of sodium hydroxide is known to contain contaminants sodium chloride and magnesium chloride. A 4.599 gram sample of this supply is dissolved and diluted to 1000 ml with water. A 20 mL of this solution is titrated with 22.26 mL of a 0.1986 molar solution of hydrochloric acid. What percentage of the original sample is sodium hydroxide? It is best to assume that none of the sodium chloride and magnesium chloride reacted with the hydrochloric acid