Problema Solution
A pharmacist poured a 4% NaCl solution into a flask already containing NaCl solution of unknown concentration. If the total volume of the mixed solution in the flask is 200mL and its concentration is 2.5% NaCl, how many milliliters of the 4% solution was poured into the flask?
Answer provided by our tutors
4% NaCl solution: x
So
4%x = 200*2.5%
x = 125
So 4% NaCl solution is 125 ml