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2014-11-18T13:02:46+02:00
100 g solutie.................15 g .............85 g apa
150 grsolutie..................x g substanta.............yg apa

x=15x150/100=22.5 g substanta

y=127.5 g apa 
daca se evapora 25 g apa raman 127.5-25=102.5 g apa

102.5+22.5 g subst=125 g solutie ramasa dupa evaporare

125 g solutie................22.5 g subst
100g solutie.................z g subst

z=2250/125=18   

deci conc solutiei obtinute e 18%

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