## Adding OH- and H20 into reactions

Marina Gollas 1A
Posts: 36
Joined: Fri Sep 28, 2018 12:20 am

### Adding OH- and H20 into reactions

How do we know when we need to add OH- and H20 into the equations that take place in basic solutions? I know we need to add them to balance out the O's and H's in the reactants, but how do we know when to use OH- instead of H20, since my problem is that I use H2O instead of OH-. Thank you.

Angel Chen 2k
Posts: 59
Joined: Fri Sep 28, 2018 12:20 am

### Re: Adding OH- and H20 into reactions

In basic solution, you first balance O by using H2O, then balance H by adding H2O to the side of each half-reaction that needs H , and then add OH - to the other side of the equation

Marina Gollas 1A
Posts: 36
Joined: Fri Sep 28, 2018 12:20 am

### Re: Adding OH- and H20 into reactions

Angel Chen 2k wrote:In basic solution, you first balance O by using H2O, then balance H by adding H2O to the side of each half-reaction that needs H , and then add OH - to the other side of the equation

Thank you! So we use H20 first to try to balance the O and then next we use it to balance the H, and then what's left over that we need to balance, we use OH-? Just like that?:)

varunhariharan
Posts: 30
Joined: Mon Jan 07, 2019 8:16 am

### Re: Adding OH- and H20 into reactions

For a basic solution, H2O is added to balance the O atoms in the balanced equation. Next, H2O is added to balance the Hydrogens, and OH- is added to the other side of the equation to make up for the excess Hydrogen atoms.