[oksijen]

Hi, I have a problem. Can you help me?

I want to prepare mixture from two compounds. one of this 0.2 molar composition and the other is 0.8 molar composition. I know their molecular weight and weight. How can I calculate this? please help

[Borek]

I am not sure I understand what you are trying to achieve, but I am more then sure that CASC will be helpfull

PLease be more specific as to what you have and what is your target solution.

[Gman4554]

This is striaght forward if I am reading your question correctly.

Molarity is moles/liter and moles is the mol wt of compound in gms in a liter of solvent.

Therefore if you want 0.2moles = 0.2 x mol wt of cmd A and 0.8 x mol wt of cmd B.

weigh them into a one liter flask and qs with solvent of your choice.

You also stated you have already weighed them out. If that is the case then whatever the weights are just divide them by their respective mol wts and you will have their molar concentrations.

For example 0.2 molar KI is 0.2 x 166 in a liter or 33.2gms KI/liter.