# chemistry a level help!!

can someone explain why this goes from 4 particles to 7?
i don't understand how there's 4 to begin with
https://imgur.com/a/SRkkH6B
it seems that there is an issue with the image, could you describe it?
Original post by zoella A
it seems that there is an issue with the image, could you describe it?

Na2C2O4(aq) reacts with [Fe(H2O)6]3 and the entropy increases from 4 ---> 7 particles ?
What's the product of the reaction?
As in order to determine entropy you need to compare the total moles of products and the total moles of the reactant?
(edited 1 year ago)
Original post by zoella A
What's the product of the reaction?
As in order to determine entropy you need to compare the total moles of products and the total moles of the reactant?

the produt makes sense sort of, since 6h2o + [Fe(C2O4)] forms, but i dont get where the extra two particles are in the reactant moles
Well given that the equation is, and im assuming it is, Na2C2O4(aq) + 3Fe(H2O)6 ---------- 6h2o + [Fe(C2O4)]
the sum of the total moles of the reactant is 4 moles whilst the sum of the total moles of products is 7 moles and so entropy increases, as the no. of moles/ particles increases by an addition of 3 moles thus greater no. of ways for the particles to be arranged and so increase in disorder.
Original post by zoella A
Well given that the equation is, and im assuming it is, Na2C2O4(aq) + 3Fe(H2O)6 ---------- 6h2o + [Fe(C2O4)]
the sum of the total moles of the reactant is 4 moles whilst the sum of the total moles of products is 7 moles and so entropy increases, as the no. of moles/ particles increases by an addition of 3 moles thus greater no. of ways for the particles to be arranged and so increase in disorder.

thank you, but i still dont understand where 3 moles of Fe(H2O)6 came from and also wouldn't that make the equation unbalanced since there's only one mole of Fe in the products?
Original post by cheribebe
can someone explain why this goes from 4 particles to 7?
i don't understand how there's 4 to begin with
https://imgur.com/a/SRkkH6B

The reaction is:

[Fe(H2O)6]3+ + 3[C2O4]2- ==> [Fe(C2O4)3]3- + 6H2O

As you can see there are 4 particles on the left and 7 on the right.

When sodium ethandioate is dissolved the ethandioate ions are separated from the sodium ions (these are spectator ions in the process)

The ethandioate ion is a bidentate ligand and so forms a tris- complex with a transition metal ion, [Fe(C2O4)3]3-
The water ligands are released into the solution, increasing the overall entropy change.
Original post by charco
The reaction is:

[Fe(H2O)6]3+ + 3[C2O4]2- ==> [Fe(C2O4)3]3- + 6H2O

As you can see there are 4 particles on the left and 7 on the right.

When sodium ethandioate is dissolved the ethandioate ions are separated from the sodium ions (these are spectator ions in the process)

The ethandioate ion is a bidentate ligand and so forms a tris- complex with a transition metal ion, [Fe(C2O4)3]3-
The water ligands are released into the solution, increasing the overall entropy change.

thank you so much
so ethandioate is bidentate but it forms 3 bonds with iron?
Original post by cheribebe
thank you so much
so ethandioate is bidentate but it forms 3 bonds with iron?

Where do you see three bonds?

Bidentate means that each ethandioate forms two bonds to the transition metal ion.
There are three ethandioate ligands = 6 bonds (octahedral)