Question

Calculeaza concentratia procentuala a solutiei care se obtine prin dizolvarea a 0,2 moli clorura de sodiu in 117 g solutie clorura de sodiu 15%.

Answer 1

c1=md1/ms1 *100

c2=md2/ms2*100
c1=15%
ms1=117
md1=c1*ms1/100=15*117/100=17.55g NaCl
md2=md1+mNaCl
ms2=ms1+mNaCl
nNaCl=m/M>>>m=n*M=0,2*58.5= 11,7g
MNaCl=23+35,5=58,5
md2=17,55+11,7=29,25g
ms2=117+11,7=128,7
c2=29,25/128,7*100=22,72%