Masa NaClO
Submitted by Serdjo on Sun, 02/09/2014 - 16:48

Forums:
Nepoznata masa NaClO je rastvorena u vodi, tako da je ukupna zapremina rastvora 2,00dm^3. pH rastvora je 10,5. Koliko je g ove soli rastvoreno u vodi? Kb= 3,3 * 10^-7 moldm^-3
NaClO+H2O--------------->HClO
NaClO+H2O--------------->HClO+NaOH
HClO+H2O--------------->ClO- + H3O+
ClO-+H2O----------------->HClO+OH-
{H+}=3.16*10(-11) mol/l
Kb={HClO}*{OH-}/{ClO-}
{OH-}=Kw/{H3O+}=1*10(-14)/3.16*10(-11)=3.16*10(-4) mol/l
{HClO}={OH-}=3.16*10(-4) mol/l
3.3*10(-7)=(3.16*10(-4))*2/{ClO-}
{ClO-}=0.302 mol/l
NaClO------------------->Na+ + ClO-
{NaClO}={ClO-}=0.302 mol/l
n(NaClO)={NaClO)/Vu=0.302/2=0.151 mol
m(NaClO)=n(NaClO)*Mr=0.151*74.5=11.25 g