Question

Subiectul E problema 1 și 5 vă rog :3.

Answer 1

1.E) Notez "*" înmulțire si "/" împărțire
MNH4Cl=14+4*1+35.5=53.5g/mol
MNaOH=23+16+1=40g/mol
53.5g........40g
NH4Cl + NaOH = NH3
xg..............49g
x=49*53.5/40=65.53g NH4Cl
+ H2O + NaCl
Vs=200ml(cm3)
Cp=20%
ro=1.225g/cm3
ro=ms/Vs=>ms=ro*Vs=1.225g/cm3*200cm3=245g
Cp=md/ms*100=>md=Cp*ms/100=20*245/100=49g

5) md=80mg=0.08g
NaOH + H2O = Na+ OH- + H2O
VH2O=100ml(cm3)=0.1L
Vs=200ml(cm3)=0.2L
Cm=md/M*Vs=0.08/40*0.1=0.02 mol/L=10*10^-2 mol/L
pOH=2
PH=12