ms1 = 200 kg, w1% = 60%
ms2 = ms1 - m.apa,
w2% = 96%
stim ca w% = mdx100/ms
=> md = este acelasi in ambele solutii
= ms1xw1%/100
= 200x60/100 = 120 g acid sulfuric
ms2 = mdx100/w2%
= 120x100/96 = 125 g sol. finala dupa evaporare
=> m.apa = ms1 - ms2
= 200 - 125 = 75 g apa evaporata
ro apa = 1 g/ml
ro = m/V => V = roxm
= 75 ml apa