Potassium permanganate, KMnO4, is both effective at treating water and has medical uses.

Question

Potassium permanganate, KMnO4, is both effective at treating water and has medical uses. A certain solution of KMnO4 being prepared to treat water has a concentration of 11.79% (m/v). Calculate the molar concentration of 11.70% (m/v) Potassium permanganate.

PLEASE HELP. I WILL REALLY APPRECIATE IT. THANK YOUU!!

Answer 1

Molar concentration (M) is expressed as moles KMnO₄ per liter of solution.

You've written 2 different m/v concentrations of 11.79 % and 11.70 %. I'll use the 11.70% to illustrate how to answer this problem.

11.70% (m/v) means 11.70 g KMnO₄ / 100 mls of solution.

Converting this to 1 liter of solution (1000 mls), we have 11.70 g / 100 mls x 1000 mls = 117.0 g KMnO₄

Converting this to moles of KMnO₄ we have

117.0 g KMnO₄ x 1 mol KMnO₄ / 158.0 g = 0.7405 mols KMnO₄

Molar concentration = 0.7405 mol / L = 0.7405 M