Răspunsuri

2014-09-28T16:30:44+03:00
Md1=c ori ms/100=6 ori 112 /100=6,72 g NaCl
30 ml apa=30 g apa pentru ca apa are densitatea 1g/cm3
c final=md1+md2/ms1+ms2 ori 100=6,72+4/112+34   ori 100=10,72/146  ori 100=7,34%

ms2=m apa +md2=30+4=34g

BAFTA LA SCOALA!!!
2014-09-28T20:48:30+03:00
C%=md/ms * 100 => md1 = 112*6/100=6,72 g NaCl
ms 2 = ms1+m apa + md2 = 112+30+4 = 146 g NaCl
md2 = md1+4 = 6,72+4=10,72
c% finala = md2/ms2 * 100 = 10,72/146 * 100 = 7,34%