[sarah1004]

I am confusing on this problems.
Could you please help me that how to do this one?


Thanks

[Unknown008]

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]

so if I used L

its going to be 0.040mol/1000L=0.00004M?

Thanks

[Unknown008]

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]

Now the one you posted, 0.04 mol/1000L yes, that would make 0.00004M

[sarah1004]

so 0.040mol/1mL=0.04M
0.040mol/1000L=0.00004M

sorry :o

[Unknown008]

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]

so 0.040mol/1L=0.04M
0.040mol/1000mL=0.00004M

[Unknown008]

No, if you put 0.04 mol/1000 mL, you have 0.04 M

[sarah1004]

40mole/1000mL=0.04M

?

[Unknown008]

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]

So answer is just like 0.04mol/L and 0.04mol/1000mL , these?

[pramod awasthi]

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]

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]

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]

Yes 0.040moles is correct >.<