Question

Se amesteca 30 g sol. KOH 40% cu 50g sol.KOH 20% si 100g H20. Ce concentratie procentuaa va aveea solutia finala?
Va rog ajutati-ma!

Answer 1

ms1 = 30 g, c1 = 40%

ms2 = 50 g, c2 = 20%

mapa = 100 g

stim ca ms = md + m.apa

si c% =mdx100/ms

md1 = ms1xc1/100

= 30x40/100 = 12 g

md2 = 50x20/100 = 20 g

ms.final = ms1+ms2+m.apa

= 30+50+100 = 180 g

md.tot = md1+md2 = 12+30 = 42 kg

=> c%. final = mdx100/ms. final

=> c = 32x100/180 = 17,8%