Quick Question about a Concentration Problem

[Lori]

Homework Statement

Homework Equations

M = n/1 L

The Attempt at a Solution

I was wondering if the answer is 6E. I'm not too sure about what the question is asking but i do know that the more moles there are, the more concetration of ions there will be. So, E seems like the answer since it has more atoms in the compounds. Is my logic correct?[/B]

 

[DoItForYourself]

Hi,

Practically, (in P=atmospheric and T=25°C) the dissociations that you need to take into consideration (compare) are B and C. Methanol (D) does not dissociate and acetic acid (E) dissociates only partially in water. Finally, BaSO₄ (A) is not soluble in water.

 

[Borek]

No need for Ksp here. At 1 mol/L you can safely assume both CaCl₂ and NaNO₃ to be fully soluble and BaSO₄ to be not soluble at all. Then, it is just a matter of number of ions produced during dissociation (writing the dissociation reaction equation will help if you don't see it immediately).

CH₃COOH is acetic acid (not an alcohol!). It definitely dissociates, but as it is a weak acid, only partially. Safe to assume no more than just few % will be dissociated (actually just a few tenths of a %).

 

[DoItForYourself]

Sorry, my bad, of course acetic acid is not an alcohol.

Post #2 has been edited in order to be correct.

 

[Lori]

No need for Ksp here. At 1 mol/L you can safely assume both CaCl₂ and NaNO₃ to be fully soluble and BaSO₄ to be not soluble at all. Then, it is just a matter of number of ions produced during dissociation (writing the dissociation reaction equation will help if you don't see it immediately).

CH₃COOH is acetic acid (not an alcohol!). It definitely dissociates, but as it is a weak acid, only partially. Safe to assume no more than just few % will be dissociated (actually just a few tenths of a %).

If I were to count the ions for CaCl2 would be be 3 ions? Because Cl disocciates into 2 ions

 

[Borek]

If I were to count the ions for CaCl2 would be be 3 ions? Because Cl disocciates into 2 ions

Three ions, yes. Not sure what you mean by "Cl dissociates into two ions". There ARE two moles of Cl^- ions per each CaCl₂ mole, there is no "Cl" (nor "Cl₂" for that matter) that can dissociate.

 

[Lori]

Three ions, yes. Not sure what you mean by "Cl dissociates into two ions". There ARE two moles of Cl^- ions per each CaCl₂ mole, there is no "Cl" (nor "Cl₂" for that matter) that can dissociate.

Oh. How would the acetic acid work. i could the ions

 

[Borek]

Oh. How would the acetic acid work. i could the ions

English please.

Acetic acid dissociates according to the equation

CH₃COOH ↔ CH₃COO^- + H⁺

but it dissociates only partially (it is an equilibrium reaction, judging from your other questions something you have probably not yet heard about).