00:01
To balance this reaction in basic solution, i'll use the half reaction technique and balance it first in acidic solution and then convert it to basic.
00:09
We have the nitride ion as one half reaction going to ammonia.
00:15
We first make sure the nitrogens are balanced.
00:17
There's one on each side.
00:19
We then balance the oxygens with water.
00:22
We've got two oxygens on the left hand side, so we'll need two waters, each one giving us one oxygen on the right hand side.
00:31
That introduces four hydrogens plus the three that are here is going to require seven h pluses on the left hand side.
00:40
Then to make sure the charges are the same on both sides, we need to add six electrons so that both sides have no charge.
00:49
Then we'll balance the aluminum half reaction where aluminum goes to alo2 minus.
00:57
First we make sure the aluminums are balanced, which they are one and one.
01:01
We'll then add two waters to the left hand side so we have two oxygens on both sides.
01:07
That introduced four hydrogens so we'll need to add four h pluses.
01:14
Then to balance charges, we've got no charge over here and a plus four, uh sorry, a minus sorry, plus three on this side.
01:22
So that means we need three electrons so that both sides have a charge.
01:28
Then we need to add these two reactions together so the electrons cancel.
01:32
We'll multiply this by two and then we get six electrons canceling.
01:38
Summing these up, we get seven hydrogens.
01:42
This is two times four, that's eight hydrogen.
01:45
So we actually have a net h plus on the right hand side and then we've got one no2 minus on the left hand side.
01:58
We've got two waters times two, that gives us four waters...