Page 1 of 1

Balancing half reactions

Posted: Tue Feb 18, 2020 7:04 pm
by Clara Cho 2K
When you put the two half reactions together should the electrons cancel each other out?

Re: Balancing half reactions

Posted: Tue Feb 18, 2020 7:08 pm
by KeyaV1C
I’m not too sure if I understand your question, but when you’re balancing redox reactions when you’re given individual reactions, you need to make sure the electrons cancel out.

Re: Balancing half reactions

Posted: Tue Feb 18, 2020 7:24 pm
by 105311039
Yes you should be able to cancel out the electrons when you combine both half equations.

Re: Balancing half reactions

Posted: Tue Feb 18, 2020 9:16 pm
by Joseph Saba
Make sure that the amount of electrons transferred are all accounted for on the other side of the equation

Re: Balancing half reactions

Posted: Tue Feb 18, 2020 9:18 pm
by Venus_Hagan 2L
Yes, the number of electrons lost in one reaction should equal the number of electrons gained in the other.

Re: Balancing half reactions

Posted: Wed Feb 19, 2020 1:48 am
by Eunice Nguyen 4I
When you combine the two half reactions together, the electrons on both sides should cancel each other out, so make sure that they're equal to one another before combining.

Re: Balancing half reactions

Posted: Wed Feb 19, 2020 2:22 pm
by Chantel_2I
Yes, they should cancel out, which is why we must balance the reduction and oxidation reactions, to make sure the number of electrons on the left is equal to the number of electrons on the right.

Re: Balancing half reactions

Posted: Wed Feb 19, 2020 2:32 pm
by Brandon Valafar
Yes! They do cancel out. We balance out the reactions so there is the same number of electrons lost on one side are gained on the other for them to cancel.

Re: Balancing half reactions

Posted: Wed Feb 19, 2020 4:08 pm
by Pablo 1K
Yes! Ensure your charges on both side equal as electrons cancel out.

Re: Balancing half reactions

Posted: Wed Feb 19, 2020 4:31 pm
by Jessica Kwek 4F
When balancing half reactions, make sure that your electrons cancel out. They would cancel as long as the number of electrons on both sides are equal to each other.

Re: Balancing half reactions

Posted: Thu Feb 20, 2020 11:20 am
by Viviana Velasquez
Yes, you have to cancel out the electrons on both sides. Most times you'll have to multiply at least one of the half reactions in order to get the same amount of electrons on each side to be able to cancel them out.

Re: Balancing half reactions

Posted: Thu Feb 20, 2020 11:43 am
by Abby Soriano 1J
We haven't talked much yet about properly balancing half-reactions, but I know that there are a lot more steps involved, such as adding H2O to balance any oxygens and adding H+ to balance any hydrogens. The number of electrons you add should be to properly balance the charges on both sides, and yes the number of electrons for each half-reaction should equal each other (you can multiply one half-reaction by a certain factor to get them to equal each other) so that they cancel out. Prof Lavelle might discuss this further (or not!) so I wouldn't worry too much about it!