# How to calcualate moles of ions in hard water?

hey

average titre:9.69mL
EDTA:0.01000M
calculation of ca2+ moles in the 10mL hard water sample and ppm

not sure how to but here is my attempt
(0.00969L)(0.01000M)(.0010L)  does that look right
or do i leave the 10mL out?

my average EDTA titration:13.65mL
calculate total moles of Mg2+ + Ca2+ in the 10mL hard water sample

since its the EDTA to Ca2+ is a 1:1
do i take the moles from the calcium and multiple it by the volume of EDTA x 10mL?

CALCULATION OF Mg2+ moles in the 10mL hard water sample
EDTA-Ca2+=Mg2+ so if i find the top two subtract it from each other and get magnessium?

### Re: moles

I am not really following your data. Could you please give me some more data and some sample calculation you have done?

### Re: moles

ppm is usually mg/L but when you have moles and no mg how do you substitue them?

### Re: moles

you have to convert the moles to grams by using the atomic or formula weight of whatever species you are looking for..... the # of moles times the formula weight will give you the number of grams

the number of grams times 1000 will give you the milligrams