I need to make a solution that contains PAH (paraaminohippuric acid) at 25mmol/liter.

So as suggested I did like this

1. 25mmol/l divide by 1000=0.025mol/l

2. 0.025 mol/l x the MW of PAH which is 194.19g/mol =4.85475

does this mean i need to dissolve 4.85475 g of PAH in one liter to get the 25mmol/liter

However i have found out that i have little amounts of PAH

so I want to make just 100ml with a concentration of 25mmol/liter

So do i just do some ratio and proportion like:

4.85475 g PAH/1000ml =X g PAH/100ml =0.485475 g of PAH

Thus i just need to mix 0.485475 g of PAH then fill up to 100 ml

Is the concentration still 25mmol/ liter?

thanks