Question

Salutare am nevoe sa rezolv o problema si nustiu cum so fac.
5kmoli de acid sulfuric H2So4 reactioneaza cu solutia de hidroxid de sodiu,de concentratie 20%.
Ce masa de solutie de NaOHeste necesara?

Answer 1

$H_{2}SO_{4} + 2NaOH -> Na_{2}SO4 + 2H_{2}O$

1 mol H2SO4 reacţionează cu .................... 2 moli NaOH
5 kmoli H2SO4 .............................................. x= 10 kmoli NaOH

Aplicăm concentraţia de 20%:

$10 \ kmoli * \frac{100}{20} = 50 \ kmoli \ NaOH = 2000 \  kg \ NaOH$

Answer 2

2 NaOH + H2SO4 ---> Na2SO4 + 2 H2O
1 mol H2SO4........2*40 g NaOH
5 kmoli H2SO4.........x kg NaOH         x = 400 kg NaOH
c%=md/ms*100=>ms=md/c*100=400*100/20=2000 kg NaOH

masa molara NaOH = 23+16+1=40g/mol
masa molara H2SO4 = 2*1+32+4*16=98 g/mol