116. Solving a chemistry problem

116. Solving a chemistry problem

3. Iron sol (Fe(OH)3) v=11 ml protected with sodium caseinate solution (ω=0.5%). What is the iron number if coagulation of the sol with a solution of potassium sulfate (C = 0.01 mol / l) occurs with the addition of 0.4 ml of sodium caseinate solution, and with 0.3 ml it still does not exist?

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