Redox question

11

Here's the question and I don't know what to do:

Iron in food, in the form of $Fe^3^+$ reacts with ascorbic acid $C_6H_8O_6$ (vitamin C), to form dehydroascrobic acid, $C_6H_6O_6$

(a) Write an ionic half equation to show the conversion of the ascorbic acid to dehydroascorbic acid in aqueous solution

(b) In the other ionic half-equation $Fe^3^+$ is converted to $Fe^2^+$ . Deduce the overall equation for the reaction between $C_6H_8O_6$ and $Fe^3^+$

Reply 1

lanky2610

2

a) in the first question C6H8O6 is losing 2 H^+ ions to become C6H6O6. So your half equation should be showing C6H8O6 and 2 electrons going to C6H6O6 and 2H^+.
b) Fe^3^+ becomes Fe^2^+ by gaining 1 electron. Times this by 2 to get an equal charge on both half equations:
2Fe^3^+ + C6H8O6 goes to 2Fe^2^+ + C6H6O6.

All that needs to be done is balance the 2 equations so that the overall loss or gain of electrons is 0 and add the 2 equations together

Reply 2

charco

Study Forum Helper

18

lanky2610

a) in the first question C6H8O6 is losing 2 H^+ ions to become C6H6O6. So your half equation should be showing C6H8O6 and 2 electrons going to C6H6O6 and 2H^+.
b) Fe^3^+ becomes Fe^2^+ by gaining 1 electron. Times this by 2 to get an equal charge on both half equations:
2Fe^3^+ + C6H8O6 goes to 2Fe^2^+ + C6H6O6.

All that needs to be done is balance the 2 equations so that the overall loss or gain of electrons is 0 and add the 2 equations together

not quite..
C6H8O6 --> C6H6O6 + 2H+ + 2e

Reply 3

lanky2610

2

My error. Sorry! :smile:

Redox question

Related discussions

Articles for you

How The Student Room is moderated