#1
This is probably a very basic problem but my mind has gone blank, so I apologise in advance :P

Suppose I had a compound X. I measured out a weight of it such that there were 0.6 moles of it. I then added it to 10 ml of water to make a solution of it.
(So the concentration of it in the 10 ml of water would be 60moldm^-3, right?)

Next, I only want 1 ml of the solution, so I take it 1ml of it out and put it into a beaker, already containing say 10 ml of a different solution. What would be the concentration of the solution of compound X in the beaker?

0
8 years ago
#2
(Original post by lauram992)
This is probably a very basic problem but my mind has gone blank, so I apologise in advance :P

Suppose I had a compound X. I measured out a weight of it such that there were 0.6 moles of it. I then added it to 10 ml of water to make a solution of it.
(So the concentration of it in the 10 ml of water would be 60moldm^-3, right?)

Next, I only want 1 ml of the solution, so I take it 1ml of it out and put it into a beaker, already containing say 10 ml of a different solution. What would be the concentration of the solution of compound X in the beaker?

This is assuming compound X hasn't undergone any reactions, right?

60 mol dm^-3 should be right. (That number is really high though, not sure if it's realistic )

In 1ml of the solution there would be (60 * 0.001 = 0.06) mol.

(I realise I'm using a sort of round-about method here, but hopefully it helps you understand )

Since you're adding 1 ml to 10ml of a different solution, you'll end up with a total of 11ml.

You now have 0.06 mol of Compound X in the 11ml solution.

Conc. of X in the solution = 0.06/0.011 mol dm^-3

Sorry if I've gone wrong anywhere
0
#3
(Original post by LetoKynes)
This is assuming compound X hasn't undergone any reactions, right?

60 mol dm^-3 should be right. (That number is really high though, not sure if it's realistic )

In 1ml of the solution there would be (60 * 0.01 = 0.6) mol.

Since you're adding 1 ml to 10ml of a different solution, you'll end up with a total of 11ml.

You now have 0.6 mol of Compound X in the 11ml solution.

Conc. of X in the solution = 0.6/0.011 mol dm^-3

Sorry if I've gone wrong anywhere
Thanks, but when you take the 1ml out, you wouldn't be removing the whole 0.6 moles, would you? :P
0
8 years ago
#4
(Original post by lauram992)
Thanks, but when you take the 1ml out, you wouldn't be removing the whole 0.6 moles, would you? :P
Woops sorry lol, had it right at first then edited it and made it wrong re-edited it, should be okay now
0
#5
(Original post by LetoKynes)
Woops sorry lol, had it right at first then edited it and made it wrong re-edited it, should be okay now
Ahh ok, thanks for your help
0
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