00:01
Okay, this question is asking, it's possible to bounce a bit of paper clip on the surface of water and a beaker.
00:05
If you add a bit of soap to the water, however, the paperclip sinks.
00:08
Explain how the paperclip can float and why it sinks when soap is added.
00:12
First of all, this question is referring to intermolecular forces and specifically the intermolecular forces of water.
00:20
So let's draw this beaker here.
00:22
We have this paper clip that's floating on top.
00:24
And it's true.
00:25
If you just level out and you increase the surface area of the papercliff, so you don't put it up and down.
00:30
But you make it as flat as possible on the surface, the paper clip can float.
00:35
And this is a unique property from water.
00:37
And water, the structure, has oxygen as, so if i draw the lewis structure, oxygen is in the center.
00:45
It's got two lone pairs of atoms and hydrogen's on either side of it.
00:50
And this is a bent structure.
00:52
It's very asymmetrical.
00:53
And not only is it bent, but you have some polar bonds here.
00:57
So the electronegativity is different enough that you have a polar bond and the structure is asymmetrical.
01:02
So you're creating an overall dipole of a negative charge here and a positive or a positive charge here.
01:08
So when one molecule of water is attracted to another molecule of water, that's called an intermolecular force.
01:14
So interme means between two particles, like a water and a water molecule.
01:18
The way water is attracted to water is by these partial charges here, so these dipoles here.
01:24
So when we answer this question, what it's basically asking is why, once you add soap to the system, why does the paperclip start to sink? so it's very important to know what water looks like when it's all together.
01:37
So when i draw water again, i'm going to draw, here's my oxygen, and there's my two hydrogens, and then i'll do it again.
01:47
Let me erase that.
01:49
So here's my two hydrogens, and then my oxygen again...