Question

calculati concentratia a 160 g de solutie, daca prin evaporarea apei se obtine 40 g de sare de masa

Answer 1

c = md*100/ms
c = 40*100/160 = 25%

Answer 2

[tex] \frac{c}{100} = \frac{m_d}{m_s} ~unde:m_d=masa~dizolvant(sare)\\ ~~~~~~~~~~~~~~~~~~~~~~~~m_s=masa~solutiei\\\\ Din~relatia~de~mai~sus~obtinem~ecuatia:\\ \frac{c}{100} = \frac{40}{160} =\ \textgreater \ c= \frac{40*100}{160} =\ \textgreater \ c= \frac{100}{4} =\ \textgreater \ c=25[/tex]