Răspuns :
sper ca te am ajutat
( md= masa dizolvat
( ms=masa solutie
(C=concentratia
[tex]\dfrac{masa \ sare}{masa \ solutie} = 5\% \implies \dfrac{m_d}{250} = \dfrac{5}{100}[/tex]
[tex]m_d = \dfrac{250 \cdot 5}{100} = \dfrac{1250}{100} = 12,5 \ g[/tex]
sau:
5 ........ 100
x ..........250
[tex]x = \dfrac{250 \cdot 5}{100} = \dfrac{1250}{100} = 12,5 \ g[/tex]