- [Instructor] In a previous video,
we used a particulate model like this
to understand a reaction,
not just to understand the reaction,
but to balance the chemical reaction as well.
And when I hand drew these particles,
the atoms in this particulate model here,
I tried to draw it pretty close
to their actual relative sizes.
Carbon atoms are a little bit bigger than oxygen atoms,
and they're both a lot bigger than hydrogen atoms.
What we're gonna do in this video
is extend our understanding using a particulate model
to start to visualize what actually might go on
in a mixture
of some of these reactant molecules.
So what I have here on the left-hand side
are the various molecules.
I have two methane molecules here.
I have three water molecules.
And what I wanna do with you
is draw what we would expect to see after the reaction.
And I encourage you, like always, pause this video
and see if you can have a go at that,
maybe with a pencil and paper,
at least just try to imagine it in your head,
before I do this with you.
All right, now, let's do this together.
Now, we know that for every methane and every water,
we're going to produce one carbon monoxide
and three molecular hydrogens.
And each of those molecules of hydrogen
have two hydrogens in them.
So let's just say that this one and this one react.
They're going to produce one carbon monoxide.
I'm gonna try to draw the relative sizes roughly, right?
So one carbon monoxide.
And then they're gonna produce six hydrogen atoms
that are going to be in three hydrogen molecules.
So let's do,
that's two and four,
and then I'll just do one here
and then six.
All right, so I took care of this one and this one.
And now we can imagine that maybe this water molecule
reacts with this methane molecule,
and so that would produce another carbon monoxide.
Let me draw that
roughly at the right size.
Another carbon monoxide molecule
and three more hydrogen molecules
for a total of six more hydrogens.
So that's one and two
and three.
And now we have this water right over here
that had no one to react with in this situation,
had no partner.
And so that's just going to be a leftover reactant molecule.
So let me just draw it right over here.
So that water could be
right over right over here.
And so this was a useful way
of starting to visualize what might be going on.
Remember, this is happening at a very high temperature.
They're all bouncing around, et cetera.
And then when they react, you might get this,
but then this water molecule has no one to react to,
so it is, you could view it as a leftover
after the reaction.