H+, OH-, water

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rkang00
Posts: 69
Joined: Fri Sep 28, 2018 12:25 am

H+, OH-, water

Postby rkang00 » Thu Feb 28, 2019 3:19 pm

If there are H+ or OH- or water left over from balancing half-rxns, do we have to list them in the cell diagram as well?

Brian Chhoy 4I
Posts: 66
Joined: Fri Sep 28, 2018 12:16 am

Re: H+, OH-, water

Postby Brian Chhoy 4I » Thu Feb 28, 2019 3:24 pm

I would think that you would need to include the H+ and OH- in the cell diagrams, but I dont think water is included.

Danny Zhang 4L
Posts: 62
Joined: Fri Sep 28, 2018 12:26 am

Re: H+, OH-, water

Postby Danny Zhang 4L » Thu Feb 28, 2019 7:03 pm

You will only need to include H+ and OH-.

Zubair Ahmed 1L
Posts: 81
Joined: Fri Sep 28, 2018 12:16 am

Re: H+, OH-, water

Postby Zubair Ahmed 1L » Thu Feb 28, 2019 9:22 pm

You will only need to include H+ and OH- in the cell diagram; exclude water.

MadelynNguyen1F
Posts: 59
Joined: Fri Apr 06, 2018 11:04 am

Re: H+, OH-, water

Postby MadelynNguyen1F » Thu Feb 28, 2019 9:37 pm

A previous chem community post stated, "it seems that the elements/molecules are included that contribute to an oxidation number change or the overall charge on a side of a reaction.
H+ and the other ions contribute to charge difference and therefore, electron balance.
The neutral NO2(g) molecule is important because it has a different oxidation number for N than NO3-(aq).
H2O doesn't really do much because it is neutral and doesn't contribute to electron balance and the oxidation number of either element doesn't change from one side of the reaction to another"

makenzie2K
Posts: 31
Joined: Fri Sep 28, 2018 12:20 am

Re: H+, OH-, water

Postby makenzie2K » Sat Mar 02, 2019 1:13 pm

Would we be penalized for including the presence of water in the cell diagram? If it doesn't contribute to a charge difference I don't see why we would, but I just want to make sure.

Nicole Elhosni 2I
Posts: 62
Joined: Fri Sep 28, 2018 12:28 am

Re: H+, OH-, water

Postby Nicole Elhosni 2I » Sat Mar 02, 2019 1:25 pm

You only put the elements or compounds in the cell diagram that are being oxidized or reduced. If H+ was reduced to H2, then you would put it at the cathode. But when using H+, H20, and OH- to balance redox reactions, they are not placed into the cell diagram notation.

Katie_Duong_1D
Posts: 69
Joined: Fri Sep 28, 2018 12:27 am

Re: H+, OH-, water

Postby Katie_Duong_1D » Sat Mar 02, 2019 4:06 pm

You include H+, OH-, and water when balancing equations, then cancel if they are on both sides. H2O is a pure liquid, so only include aqueous OH- and H+ are included.

Krista Mercado 1B
Posts: 60
Joined: Fri Sep 28, 2018 12:26 am

Re: H+, OH-, water

Postby Krista Mercado 1B » Sun Mar 03, 2019 3:17 pm

You would include H+ and OH-, but not H2O

Meghanhe1l
Posts: 60
Joined: Fri Sep 28, 2018 12:17 am

Re: H+, OH-, water

Postby Meghanhe1l » Sun Mar 03, 2019 3:54 pm

Water is implied in the aqueous species of your cell diagram, so you do not need to externally include them. However, the presence of H+ and OH- needs to be specified by including them in your cell diagram.


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