Bunuel wrote:
150 ml of 30% sulphuric acid was added to approximate 400 ml of 12% sulphuric acid solution. Find the approximate concentration of the acid in the mixture?
A. 1/2
B. 1/3
C. 1/4
D. 1/6
E. 1/5
total acid/total solution; (150*0.3+400*1.2)/550; 93/550; the options have a wide gap to approximate to high extent 90*100/550;9*100/50=18% (must be less than this as denominator is reduced), 1/5 itself is 20% so IMO D 1/6
