Half rxns

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605110118
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Half rxns

Postby 605110118 » Wed Mar 04, 2020 7:21 pm

What differs when balancing acidic vs basic rxns?

Ian Morris 3C
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Re: Half rxns

Postby Ian Morris 3C » Wed Mar 04, 2020 7:24 pm

with acidic you add H+, basic add oh-

Charlyn Ghoubrial 2I
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Re: Half rxns

Postby Charlyn Ghoubrial 2I » Thu Mar 05, 2020 1:40 am

Acidic: split equation in 2 half reactions and balance them (adding H2O to balance Os and H+ to balance Hs) then you cancel out your balanced electrons and anything else that needs cancelling and write your balanced equations
Basic: same steps as Acidic but then you add OH- on the side that has H+ to turn it into H2O and then subtract the least number of H2O from both sides to get your balanced equation
The organic chemistry tutor has a great video on this (they’re separate videos so make sure to search for both of them)

Celine 1F
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Re: Half rxns

Postby Celine 1F » Thu Mar 05, 2020 3:57 am

When balancing acidic solutions, you would add H2O to balance the O's and then add H+ to balance the H's out. For balancing basic solutions, you would add H2O to balance the O's and then add H2O to the other side and OH- on the opposite side. From here, you would balance electrons for both types of solutions.

Juana Abana 1G
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Re: Half rxns

Postby Juana Abana 1G » Thu Mar 05, 2020 7:16 pm

To balance acidic solutions you add H2O to balance the O's and then add H+ to balance the H's. Then you balance the electrons. However when balancing basic solutions you add H2O to balance the O's and then add H+ to balance the H's, but for every proton that you add you also add OH- to both sides of the equation.Then you balance the electrons

Jocelyn Thorp 1A
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Re: Half rxns

Postby Jocelyn Thorp 1A » Fri Mar 06, 2020 1:50 am

with acidic conditions you're balancing H2O and H+, and with basic conditions you're balancing H2O and OH-

Junwei Sun 4I
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Re: Half rxns

Postby Junwei Sun 4I » Fri Mar 06, 2020 2:13 am

When balancing acidic reactions you balance O using H2O and H with H+
When balancing basic reactions you balance O using H20 and H with H2O then adding OH- to the opposite side

Gurmukhi Bevli 4G
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Re: Half rxns

Postby Gurmukhi Bevli 4G » Sat Mar 07, 2020 12:24 am

In both cases, you are balancing O and H, when balancing acidic reactions, add H+ protons (to balance H) and H2O (to balance O), and for basic reactions, add OH- ions and H2O.

Brandi 2C
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Re: Half rxns

Postby Brandi 2C » Sat Mar 07, 2020 12:28 am

I do know that H+ is added in acidic reactions and OH- is added in basic, but I was wondering in which situations H3O+ would be used?

Madeline Phan 1E
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Re: Half rxns

Postby Madeline Phan 1E » Sat Mar 07, 2020 11:03 am

Balancing in acidic solutions means adding H+ and H2O while balancing in basic solutions means balancing with OH- and H2O

Nicholas_Gladkov_2J
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Re: Half rxns

Postby Nicholas_Gladkov_2J » Sat Mar 07, 2020 11:16 pm

605110118 wrote:What differs when balancing acidic vs basic rxns?


The difference between balancing acidic versus basic reactions is that they both are the exact same, except in the end of balancing, you will add the same amount of OH- on both sides of the balanced equation equal to the number of H+ in the reaction.

faithkim1L
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Re: Half rxns

Postby faithkim1L » Sun Mar 08, 2020 12:32 am

When balancing acidic reactions, add H+ and H20. For basic reactions, add H20 and OH-.

005384106
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Re: Half rxns

Postby 005384106 » Sun Mar 08, 2020 1:14 pm

At what point do you add elections to the half reaction?

Jeremy_Guiman2E
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Re: Half rxns

Postby Jeremy_Guiman2E » Sun Mar 08, 2020 1:24 pm

005384106 wrote:At what point do you add elections to the half reaction?


you would add electrons at the end to balance charge on both sides.

Vinita Saxena 2I
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Re: Half rxns

Postby Vinita Saxena 2I » Sun Mar 08, 2020 3:02 pm

Adding electrons is the very last step, once you add the H+ for acidic or OH-/H2O for basic you add electrons to balance out charge. When adding the half reactions together make sure to multiply the reactions if needed so the electrons are equal.

Michelle N - 2C
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Re: Half rxns

Postby Michelle N - 2C » Sun Mar 08, 2020 10:44 pm

005384106 wrote:At what point do you add elections to the half reaction?


I believe it's when you need to balance out the charges.

Eesha Chattopadhyay 2K
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Re: Half rxns

Postby Eesha Chattopadhyay 2K » Mon Mar 09, 2020 12:02 am

When the solution is acidic, you balance the hydrogen ions by adding an H+ to the other side. When the solution is basic, you balance the hydrogen by adding an H20 to the side that needs the hydrogen and a OH- on the other side so that the side with the H20 has a net higher number of hydrogens.

Sanjana K - 2F
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Re: Half rxns

Postby Sanjana K - 2F » Mon Mar 09, 2020 12:33 am

https://chem.libretexts.org/Bookshelves ... _Chemistry)/Electrochemistry/Redox_Chemistry/Balancing_Redox_reactions

Here's a pretty helpful link! In an acidic solution, the reaction is balanced after you've added your H+ to balance the hydrogens and electrons to balance charge but in a basic solution, you won't end up with H+ in your balanced reaction. Rather, for each H+, you need to add one OH-, which creates water (and then you balance charge with electrons) so your final balanced reaction in a basic solution will contain OH- and electrons.

ABombino_2J
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Re: Half rxns

Postby ABombino_2J » Mon Mar 09, 2020 12:56 am

Balance it the same as you would with acidic but add OH- at the end to cancel out the H+.

Julia Holsinger_1A
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Re: Half rxns

Postby Julia Holsinger_1A » Wed Mar 11, 2020 5:04 pm

005384106 wrote:At what point do you add elections to the half reaction?

When all other elements are balanced and you just need to balance the charge of both sides

Julia Holsinger_1A
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Re: Half rxns

Postby Julia Holsinger_1A » Wed Mar 11, 2020 5:05 pm

When balancing basic half reactions, how do you know which side to put the OH- versus the H2O?

005384106
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Re: Half rxns

Postby 005384106 » Wed Mar 11, 2020 6:14 pm

Do you always add the H2O at opposite ends of where you have added OH or H+?

205154661_Dis2J
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Re: Half rxns

Postby 205154661_Dis2J » Sat Mar 14, 2020 4:18 pm

There are two really helpful resources on Lavelle's website where it tells you what to do for acidic and basic solutions. From that, you can see what differs basic rxns from acidic rxns.

Rafsan Rana 1A
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Re: Half rxns

Postby Rafsan Rana 1A » Sun Mar 15, 2020 3:47 pm

I believe the side that has less hydrogens is the side you would add the OH because the purpose of adding it is to balance the number of hydrogen and this is only in basic solutions

Rafsan Rana 1A
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Re: Half rxns

Postby Rafsan Rana 1A » Sun Mar 15, 2020 3:50 pm

To the question : "Do you always add the H2O at opposite ends of where you have added OH or H+?"

You should be adding the h20 first and then adding OH or the H to the opposite side to balance the number of hydrogens.

vanessas0123
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Re: Half rxns

Postby vanessas0123 » Sun Mar 15, 2020 8:31 pm

Balancing acidic reactions means adding H2O to balance oxygens, and H+ to balance hydrogen.
Balancing basic reactions means adding H2O to balance oxygens, and OH- to balance everything else.

zfinn
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Re: Half rxns

Postby zfinn » Sun Mar 15, 2020 8:39 pm

with acidic you add h2o to balance oxygen and then simply h+ to balance the hydrogen, but with basic you add h2o to balance oxygen but then need to balance the hydrogens with oh-, while adding h2o to balance any additional oxygens.

Orrin Zhong 4G
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Re: Half rxns

Postby Orrin Zhong 4G » Sun Mar 15, 2020 8:41 pm

When balancing basic reactions, balance the reaction just like you would an acidic reaction, but neutralize the H+'s with OH-'s.


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