[ANCF]

If i get these three righ Ill have more 0.5 in my final grade. I've already done this but I would like to see what you have to say.


1- In a solution of one molarity (M) of NaCL, how many mols of H20 exist comparing to the numer of mols of NaCl?



2- In a solution of one molarity (M) which is the difference between the concentration of sucrose (C12H22O1) and the concentration of H2O?


3- Which is the concentration of H20 in pure water?

[Borek]

Show your results so that we can comment.

[ANCF]

1- 1mole

2- 52.58

3- 55.346 mol/L -» 55.5mol/L

[ANCF]

1- Dont have this one here, but of what i remember i assumed there were 1000mol of solute since M= n solute / 1000ml so n=1000 (M=1)

2- 52.58

3- 55.346 mol/L -» 55.5mol/L

[Borek]

1000 mol of solute is wrong, M is mol/L, not per mL.

No idea how you did 2, looks wrong.

3 seems to be OK.

[ANCF]

Yeah I've corrected the 1st one. i was using ml... that one is out. the answer is 1 mole.

Yes i realize that because i was assuming the concentration of the 3rd question but i guess i cant do that

Any ideas to the 2nd?

[ANCF]

Well the stequiometry in the reaction is 1 to 1. So considering c = n / V n = 1 and V = 1 in both cases, the difference will be 0. correct?

[Borek]

No reaction taking place, so no stoichiometry.

Honestly, the longer I think about these questions, the less sure I am how they should be done. A lot depends on the context. Are you given densities of these solution (or at least suggested that you should check them)?