pH vrednost

Submitted by Miha1999 on Sun, 01/06/2019 - 12:49
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Izracunati pH vrednost rastvora NaHS koncentracije 1*10^-2 mol/dm3.
 Resenje: pH=9,62

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milicaradenkovic - Sun, 01/20/2019 - 12:55

NaHS-------------->Na+ + HS-

HS-+ H2O------------->H2S + +OH-

Kb1=Kw/Ka1=1*10(-14)/5.7*10(-8)=1.75*10(-7)

Kb1=(H2S)*(OH-)/(HS-)

(HS-)=c(NaHS)=1*10(-2) mol/l

x=(koren(Kb*(HS-)))=4.188*10(-5)

(OH-)=4.188*10(-5) mol/l a (H2S)=(OH-)=x

pOH= -log(OH-)=4.37

pH=14-pOH=14-4.378=9.622