00:01
Here we are given an energy diagram for a chemical reaction where we have 40, 60, 80, 100, and 120.
00:16
And this is kilojoules of potential energy.
00:28
And this is the reaction pathway.
00:33
What we are seeing is we start out at 40 kilojoules and we go up to 120 and then we drop down to 60.
00:55
So is the forward reaction endothermic or exothermic? because we end up at a higher energy state, a net 20 kilojoules of energy needs to be added in.
01:07
If we're adding in energy it's endothermic.
01:11
If we were releasing energy and we ended up at a lower energy state than where we started it would be exothermic.
01:19
Delta h for the forward reaction is going to be the difference in energy between where we started and where we ended up.
01:27
60 minus 40 gives us 20 kilojoules positive...