Problema Solution
A 25-liter solution which is 10%acid is to be mixed with a 15-liter solution which is 7% acid. if a part of the mixed solutions is replaced by 10 liters of water, what would be he new solution?
Answer provided by our tutors
The quatity of acid in the mixed solutions (without replacing with water is)
q1= 10/100*25 + 7/100*15 =3.55 kg in (25+15) =40 kg total solution
this yelds a total acidity of 3.55/40 =0.08875 = 8.875 %
Now we replace 10 liters of this solution with water. The total acid in 40 (initial soution) -10(water) =30 kg (final solution) is
q2 = 8.875/100*30 =2.6625 kg acid wich in a total of 40 liters solution gives an acidity of
2.6625/40 =0.06656 = 6.656% acidity in final solution.