Question

Determinati cantitatea(moli,grame)de NaOH care se consuma cand reactioneaza cu 490g de solutie de H2SO4 de concentratie 10%
URGENTTTTT

Answer 1

-calculez masa de acid dizolvata in solutie
c=mdx100/ms---> md= cxms/100= 10x490/100= 49gH2SO4
-calculez moli de acid din aceasta masa(M=98g/mol)
n=m/M---> n= 49g/98g/mol=0,5mol H2SO4
-deduc din ecuatie moli NaOH
2mol           1mol
2NaOH  + H2SO4---> Na2SO4 + 2H2O
x=1mol........0,5mol
-calculez masa de NaOH( M=40g/mol)
m= nxM----.> m=1molx40g/mol= 40gNaOH