Balancing and Adding together Half-Rxns

Moderators: Chem_Mod, Chem_Admin

BeylemZ-1B
Posts: 95
Joined: Thu Jul 25, 2019 12:17 am

Balancing and Adding together Half-Rxns

Postby BeylemZ-1B » Tue Feb 18, 2020 11:51 am

Why do electrons have to cancel when you balance the half reactions ? (why would the electrons released by oxidation have to be the same as the number used in reduction??)

All i know is that it has to happen, but i don't quite understand why.

Brian Tangsombatvisit 1C
Posts: 119
Joined: Sat Aug 17, 2019 12:15 am

Re: Balancing and Adding together Half-Rxns

Postby Brian Tangsombatvisit 1C » Tue Feb 18, 2020 12:22 pm

there has to be a conservation of charge on the reactant and product side of the equation. If you think of an electron as an element, there has to be the same number of both the reactant and product side.

alicechien_4F
Posts: 104
Joined: Sat Jul 20, 2019 12:15 am

Re: Balancing and Adding together Half-Rxns

Postby alicechien_4F » Tue Feb 18, 2020 12:52 pm

It is similar to why we balance all other atoms in a chemical reaction. It is so that conservation of energy, and in this case, the charge of the electrons, is maintained.

Naji Sarsam 1F
Posts: 104
Joined: Sat Aug 17, 2019 12:18 am

Re: Balancing and Adding together Half-Rxns

Postby Naji Sarsam 1F » Tue Feb 18, 2020 1:38 pm

Moreover, chemical reactions are not known to just spontaneously release electrons. First, it is favorable for electrons to be bound to a nucleus since the positive nucleus attracts the negative electron. Second, the products of a chemical reaction require the same amount of electrons as the reactants

Sally Qiu 2E
Posts: 105
Joined: Fri Aug 30, 2019 12:18 am

Re: Balancing and Adding together Half-Rxns

Postby Sally Qiu 2E » Tue Feb 18, 2020 1:52 pm

the charge of electrons must be maintained; same reasoning as to why we balance equations in general

Alexandra Bartolome 2H
Posts: 102
Joined: Sat Jul 20, 2019 12:17 am

Re: Balancing and Adding together Half-Rxns

Postby Alexandra Bartolome 2H » Tue Feb 18, 2020 2:13 pm

Since oxidation and reduction reactions happen together, the number of electrons released by oxidation needs to be the same as the number of electrons used in reduction due to the fact that in chemical reactions, electrons are neither created nor destroyed.

Jasmine Fendi 1D
Posts: 108
Joined: Sat Aug 24, 2019 12:15 am

Re: Balancing and Adding together Half-Rxns

Postby Jasmine Fendi 1D » Tue Feb 18, 2020 2:25 pm

I think that the electrons have to be balanced because it is part of a redox reaction where two half-reactions are coupled. That means that the same amount of electrons are transferred from one reaction to another and the electrons cannot just be free floating.


Return to “Balancing Redox Reactions”

Who is online

Users browsing this forum: No registered users and 4 guests