View Full Version : What are concentrations of species in 0.04M sodium sulfate in water?
sarah1004
Nov 2, 2009, 09:42 AM
I am confusing on this problems.
Could you please help me that how to do this one?
Thanks
Unknown008
Nov 2, 2009, 09:51 AM
0.04 M means 0.04 moles of the compound in 1000 mL of water
0.5 M means 0.5 moles of compound in 1000 mL
Etc etc.
M is also moles per litre, so it makes xx moles in 1 litre, or in 1000 mL
sarah1004
Nov 2, 2009, 09:55 AM
so if I used L
its going to be 0.040mol/1000L=0.00004M?
Thanks
Unknown008
Nov 2, 2009, 09:59 AM
Oh no! You missed my point!
It's 0.04 moles in 1 litre, which means 0.04 moles in 1000 mL, since 1L = 1000mL
Unknown008
Nov 2, 2009, 10:01 AM
Now the one you posted, 0.04 mol/1000L yes, that would make 0.00004M
sarah1004
Nov 2, 2009, 10:02 AM
so 0.040mol/1mL=0.04M
0.040mol/1000L=0.00004M
sorry :o
Unknown008
Nov 2, 2009, 10:06 AM
Lol!!
Ok, I think you better forget what I told you.
0.04 M = 0.04 mol in 1000 mL
1.0 M = 1 mol in 1000 mL
0.005 M = 0.005 moles in 1000 mL
sarah1004
Nov 2, 2009, 10:12 AM
so 0.040mol/1L=0.04M
0.040mol/1000mL=0.00004M
Unknown008
Nov 2, 2009, 10:15 AM
No, if you put 0.04 mol/1000 mL, you have 0.04 M
sarah1004
Nov 2, 2009, 10:18 AM
40mole/1000mL=0.04M
?
Unknown008
Nov 2, 2009, 10:22 AM
40 mole / 1000 mL = 40M
1L = 1000 mL
So, 0.04mol/L is the same thing as 0.04mol/1000mL and is the same thing as 0.04 M
sarah1004
Nov 8, 2009, 04:17 PM
So answer is just like 0.04mol/L and 0.04mol/1000mL , these?
pramod awasthi
Nov 8, 2009, 11:08 PM
I am confusing on this problems.
Could you please help me that how to do this one?
Thanks
OK I think I have not understand your question but just try
mlarity=gramwt*1000/molecular wt*volume (in litr)
but molarity given means somean concentration given want to know in gramm then ti will
.04*142=5.68 gm/L
sarah1004
Nov 8, 2009, 11:26 PM
On my book, it says only like" what are concentrations of species in 0.04M sodium sulfate in water? " this.. So that's why I was confusing..
Unknown008
Nov 9, 2009, 06:59 AM
Hmm, if the question looked for the concentration in grams per litre, then that would be right. But the question itself... I don't know what is it looking for exactly.
Or perhaps the concentration of each of the ions in the solution?
sarah1004
Nov 9, 2009, 07:17 PM
Yes 0.040moles is correct >.<