# chemistry

posted by .

Hi! i'm kinda having trouble getting this.. Don't understand it really

from

Ca(OH)2 + 2HCl-----> CaCl2 + 2H2O

How do i calculate Ca+?

1) do you mean the concentration of Ca+ ion?
2) is there excess HCl? What is given?

ok

It was from a titration/ stoichiometry lab i did

it was between 0.05 mol/dm^3 HCl and saturated Ca(OH)2

The Ca(0H)2 volumes used were

23.39, 22.49 and 20.78

What was the volume of the HCl?

How did you "titrate". At what point did the "titration" end?

the volume of the HCL was 20cm^3

the HCL was titrated against the Ca(OH)2.. we were determining the solubilty product of Ca(OH)2.

WE did the experiment 3 times
and these were the readings for the volumes of the Ca(OH)2 used

23.39, 22.49, 20.78

Ok. You know the moles of HCl used (concentration x volume) watch units.
There fore, the balanced equation tells you how many moles of Ca(OH)2 were used, so the concentration of the Ca+ ion is that number of moles /volume of total water solution (acid solution and acid solution)

check my thinking, I am not certain of your setup and procedure.