00:01
For this problem, we're going to be calculating bond antelpes given chemical, or i guess, structural formulas.
00:10
We have two to do.
00:12
Letter a, here is what we are given.
00:15
I'm going to draw them.
01:00
Okay, so this is what we're given.
01:03
Now, i am going to take a moment and highlight the bonds that are common to each.
01:11
One, two, three, one, two, three.
01:16
Those bonds cancel out, if you will.
01:22
Now, in blue, i'm going to highlight those bonds that we're going to consider.
01:26
One, two, one, and two.
01:30
We look up the bond antelps in the table that's referenced in your text, and we find the delta h.
01:41
We estimate the delta h by using bonds broken minus bonds formed.
01:57
And the bonds broken will be c, c .h and cl.
02:06
Cl.
02:08
I'm going to subtract from that.
02:10
Our bonds formed should be c, c, cl, and hcl.
02:18
And we look these up.
02:20
We've got one of each, so this one's very easy.
02:24
And we get, our c h is 413.
02:27
These are kilojoules per mole.
02:33
And the clcl is 242, kilojoules per mole.
02:38
Again, we just look these up.
02:41
Subtract from that.
02:43
I'll put this in parentheses.
02:45
Add this together.
02:46
We get 655.
02:53
And our ccl is, if i don't remember which is which here...