Răspuns:
m NaOH = 8%*300 = 24g NaOH
160 2*40
CuSO4 + 2NaOH = Cu(OH)2 + Na2SO4
x 24
(2*40) g NaOH .............. 160g CuSO4
24g NaOH .................... x g CuSO4
=> x = 48g CuSO4 necesar reactiei
m CuSO4 = 48g
c% = 10%
msol CuSO4 = 100/c% * md = 100/10 * 48 = 480g sol. CuSO4 c% = 10%