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Calculate the concentration of potassium ions in the solution, in mol L^-1.Each 200 mL...

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taiiiiiiiiisun | Student, Grade 9 | Honors

Posted January 20, 2012 at 9:25 AM via web

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Calculate the concentration of potassium ions in the solution, in mol L^-1.

Each 200 mL of an electrolyte solution designed for treating dehydration contains 0.47 g of sodium chloride (NaCl), 0.30 g of potassium chloride (KCl) and 3.56g of glucose (C6H12O6).

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ndnordic | High School Teacher | (Level 2) Associate Educator

Posted January 20, 2012 at 12:05 PM (Answer #1)

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You have 0.30 g of KCl in 200 mL, so you have 5 times as much in one liter.

0.3 * 5 = 1.5 g/liter.

To determine # of moles, divide actual mass by formula mass of KCl.

formula mass of KCl = atomic mass of K + atomic mass of Cl.

You now know the # of moles of KCl in solution.  The # of moles of K ion and the number of moles of Cl ion is the same as the number of moles of KCl.

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