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A chemistry student was given a sample of a white crystalline substance, suspected to be a mixture of sodium chloride (NaCl) and potassium chloride (KCl). The student performed an analysis and found that the sample contained 64% chlorine by mass. Calculate the mass percentage of sodium chloride and potassium chloride present in the mixture.

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To solve this problem, we need to use the given information to set up a system of equations and solve for the mass percentages of sodium chloride  NaCl  and potassium chloride  KCl  in the mixture.Let x be the mass percentage of NaCl and y be the mass percentage of KCl in the mixture. Since the mixture is composed of only these two compounds, we can write the first equation as:x + y = 100   1 Next, we need to consider the mass percentage of chlorine in each compound. The molar mass of NaCl is 58.44 g/mol  22.99 g/mol for Na and 35.45 g/mol for Cl , and the molar mass of KCl is 74.55 g/mol  39.10 g/mol for K and 35.45 g/mol for Cl . The mass percentage of chlorine in NaCl is  35.45/58.44  * 100 = 60.66%, and the mass percentage of chlorine in KCl is  35.45/74.55  * 100 = 47.53%.Using this information, we can write the second equation based on the given mass percentage of chlorine in the mixture  64% :0.6066x + 0.4753y = 64   2 Now we have a system of two linear equations with two variables. We can solve this system using the substitution or elimination method. We'll use the elimination method here. First, we'll solve equation  1  for y:y = 100 - xNext, substitute this expression for y in equation  2 :0.6066x + 0.4753 100 - x  = 64Now solve for x:0.6066x + 47.53 - 0.4753x = 640.1313x = 16.47x  125.5Since x represents the mass percentage of NaCl, we have approximately 125.5% NaCl in the mixture. However, this result is not physically possible, as mass percentages must be between 0% and 100%. There may have been an error in the given information or the analysis performed by the student. Please double-check the provided data and try again.

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