Punk - 10-8-2006 at 04:32
Is there a universal formula for figuring out how many moles of an acid are in a given solution?
I know that the hydrogen chloride molecule is 36.47g per mole but how many grams of 31.45% hcl solution does it take to equal 1 mole?
jack-sparrow - 10-8-2006 at 05:08
you have to divide your needed mass of acid by its concentration:
36.47 g / 0.3145 = 116 g of solution
another example :
you need 0.5 mol of HBr but you only have 48% HBr solution
0.5 mol * 81 g/mol = 40.5 g
40.5 g / 0.48 = 84.4 g
density = 1.49 g/ mL
84.4 / 1.49 = 56.6 mL so you measure 56.6 mL or 84.4 g it is up to you.
brain freeze
Punk - 10-8-2006 at 07:27
Im not sure what the needed mass of acid is untill i figure out how much ml. or g. 1 mole of 31.45% hcl acid is.
From there I can easily figure out the amount of 31.45% needed for a certain reaction.
hmm
Punk - 10-8-2006 at 07:36
you need 1 mole of hcl but only have 31.45% solution
1 mol x 36.47 = 36.47
36.47/3.145 = 11.6g
So 11.6g of this 31.45% hcl solution is 1 mole correct?
[Edited on 10-8-2006 by Punk]
jack-sparrow - 10-8-2006 at 08:09
I mole of HCl IS 36.5 g/mol so you divide 36.5 / 0.3145 to get :
116 g of HCl solution at 31.45 %
I already gave you the answer.
Punk - 10-8-2006 at 08:55
I just needed to move my decimal.
Thanks