Question

Urgent! Reactioneaza 200g de solutie de soda caustica de concentratie 20% cu o solutie de sulfat de cupru de concentratie 30%,calculati masa de solutie de sulfat de cupru folosita ,masa de precipitat obtinuta,nr de moli de safe rezultata,masa de apa de la sfarsitul reactiei

Answer 1

C=md/ms*100=>md=C*ms/100=20*200/100=40g

ms=md+mH2O=>mH2O=ms-md=200-40=160g

2NaOH + CuSO4 => Na2SO4 + Cu(OH)2

2*40g NaOH...............160g CuSO4
40g NaOH..................x=80g CuSO4

C=md/ms*100=>ms=md*100/C=8000/30=266,666g sol. CuSO4

ms=md+mH2O=>mH2O=ms-md=266,666-80=186,666g 

m H2O final = 186,666+160=346,666g

2*40g NaOH.......................142g Na2SO4
40g NaOH...........................x=71g Na2SO4

n=m/M=71/142=0,5 moli Na2SO4