Răspuns:
Explicație:
ms= 120g sol. NaCl
c= 20%
===>md= c . ms :100
md= 20 .120 : 100=24g A
===> mapa= ms - md
mapa= 120 - 24=96 g F
===>md adaug. = 40g
c2= 40%
===>md2= md1 + md ad.
md2= 24 + 40=64g NaCl
ms2= ms1 + md ad. A
ms2= 120 + 40=160g
c2= 64.100 : 160= 40%
===> F