ro = ms/Vs
=> ms = roxVs
= 10×1,62 = 16,2 g sol.
ms1 = 16,2, c1 = 70%
din c% = mdx100/ms
=> md = ms1xc1/100
=16,2x70/100 = 11,34 g
ms2 = ms1 + m.apa, m.apa = a
C2 = 49%
=> 49 = 11,34x100/(16,2+a)
=> a = 6,94 g apa apa necesara...
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