Question

Ma ajuta cineva? dau 40 de puncte.
Chimie:
ms=300g
c=3%
+ms 1=300g
c1=25%
A)c2 ?
B)600g h2o => c3=?

Answer 1

c = md/ms * 100
md = ms * c/100
md = 300*3/100 = 9 g 
c1 = md1/ms1 * 100
md1 = ms1 * c1/100
md1 = 300*25/100 = 75 g
md2 = md + md1 = 9+75 = 84 g
ms2 = ms + ms1 = 300 + 300 = 600 g
c2 = md2/ms2 * 100
c2 = 84/600 * 100 = 14%
ms3 = ms2 + m apa
ms3 = 600 + 600 = 1200 g
md3 = md2 = 84 g
c3 = md3/ms3 * 100
c3 = 84/1200 * 100 = 7%