hmotnost HCl

c(HCl) = c(H3O+) = 10^-pH = 10^(-3,8) = 1,584*10^-4 mol/dm3
n(HCl) = c*V = 1,584*10^-4*0,25 = 3,962*10^-5 mol HCl
m(HCl) = n*M = 3,962*10^-5*36,5 = 1,446*10^-3g = 1,446mg.

OK?

jo jasne:) diki

A jeste..pH roztoku je 11,3. Určte látkovou (mol.dm-3) a hmotnostní koncentraci (g.dm-3) NaOH v roztoku.
Mr (NaOH)= 40

pOH = 14 - pH = 2,7; c(NaOH) = c(OH-) = 10^-pOH = 10^-2,7 = 2*10^-3 mol/dm3
c = n/V [mol/dm3]; m = n*M; cm = m/V [g/dm3] = n*M/V = c*M = 2*10^-3*40 = 0,08g/dm3

OK?

ok!vdaka