Question

200 g solutie acid sulfuric de concentratie 60% reactioneaza cu 200 g de hidroxid de sodiu de concentratie 20%. Demonstrati daca reactia este totala? Daca NU, care dintre cele doua substante este in exces si cu cat?

Answer 1

Rezolvare: C=md×100:ms=> md=ms×C:100 mdH2SO4=200×60:100= 120g mdNaOH=200×20:100=40 g MH2SO4=2AH+AS+4AO= 2×1+32+4×16=34+64=98g/mol VH2SO4=m:M=120:98=1,2moli H2SO4 MNaOH=ANa+AO+AH=23+16+1=40g/mol VNaOH=m:M=40:40=1mol NaOH 1mol. 2moli H2SO4+2NaOH=Na2SO4+ 1,2moli. 1 mol 2H2O NaOh este in exces:2-1=1 1-1,2=-0,2 1+(-0,2)= 0,8 moli in exces NaOH