Matter

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Mr. Andersen gives a brief description of matter. The five states of matter are also discussed.
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Transcript Provided by YouTube:

00:05
Hi. This is Mr. Andersen and in this podcast I’m going to talk about matter.
00:10
What is matter? Matter is anything that has mass and takes up space. And so we’ll say
00:15
that it has a volume. Now scientists got together and they decided to think about what was the
00:20
greatest discovery of the last 100 years? And they eventually came up with this discovery
00:25
by this scientist named Hubble. And what Hubble discovered is that no matter where he looked
00:30
in the universe, everything in the universe is red shifted. That means everything is moving
00:35
away from everything else. And so if we play that backwards through time what that led
00:40
us to is this point at which all matter began as a single point. And so that’s where we
00:45
got this idea of a big bang. That there’s been this expansion of the universe. But what
00:49
is that universe made up of? Matter. A lot of it’s actually dark matter. But that’s a
00:54
totally different story. This is a cool side note. This is called a aerogel. And so this
00:59
is a, it’s a solid but it’s an incredibly low density solid. And it’s actually made
01:07
by making a gel and then replacing that liquid inside there with a gas. And so here, it’s
01:13
cool. It’s insulating this flower from a bunsen burner which I think is pretty amazing. So
01:16
we’ll talk about states of matter in here as well. So what is matter? Matter can be
01:21
broken down into two things. It can be broken down into what are called pure substances.
01:26
And then it can be broken down into mixtures. And so everything you think of, from myself
01:31
to the air that I breathe, is one of these things. And so the first one is going to be
01:35
a pure substance. And so an example, this is helium gas. Helium gas is made up of only
01:41
one atom. And so we call that an element. Carbon, for example, carbon in a pencil that
01:46
you might be using is also an element. It’s only made up of one type of atom. As we move
01:51
up the level in pure substances, we can also have what are called compounds. And if you
01:56
have something that’s made up of, for example, one, excuse me, one or more atoms that are
02:01
put together in a specific ratio, two or more, then we have a compound. And so somethings
02:07
that you’re familiar with would be like H2O. Or water. So the water in this droplet right
02:12
here is made up of two hydrogen atoms and one oxygen. Or the glucose that’s inside this
02:17
plant right here is actually a compound as well. And so pure substances are simply elements
02:22
and compounds. But they have to be pretty pure. And that’s where they get they’re name.
02:27
Next we have what are called mixtures. And example of a mixture, one of my favorite mixtures
02:31
would be soda. This is actually Mountain Dew. Inside here, if we could look inside the can
02:36
that would be a homogeneous mixture. Homogeneous mixture means you can’t tell apart the different
02:42
parts inside it. And so if were to look inside Mountain Dew, there’s going to be water. But
02:47
there’s also going to be carbon dioxide. And there’s also going to be sugar. And there’s
02:51
also going to be caffeine. And there’s going to be yellow dye number 5 and all those things
02:56
are mixed together but you can’t tell the different parts. So we call that a homogeneous
03:00
mixture. Now most everything that you’re used to dealing with in life, like me or the computer
03:06
sitting in front of you or anything is not going to be that. It’s actually going to be
03:10
a heterogenous mixture. Heterogeneous mixture is when you can see the different parts. And
03:15
so this is blood. And so we might think that blood looks like a homogeneous mixture. But
03:19
when you get down to the level of blood, we can see red blood cells, white blood cells.
03:24
We could even get down to the level of platelets if we looked at it. And so that’s a heterogeneous
03:28
mixture. So that’s how we classify everything. Now this is a great diagram because it shows
03:33
you in the universe, this shows you the atomic number. So we’re going all the way from the
03:38
first, hydrogen, all the way up here to uranium on the far end. This is how much they naturally
03:44
exist in the universe. And what you find is that we have a lot of hydrogen and helium.
03:50
We don’t have so much beryllium. And then we have these points that kind of level off
03:54
as we go through the atomic number. Now this is a log scale. That means we have a whole
03:59
bunch of hydrogen and helium. And you might be thinking, I wonder why that is? Well the
04:04
sun, is actually, gets it’s energy from hydrogen fusing into something called helium. And that
04:12
gives off a huge amount of energy. If you’ve heard of this before, E=mc^2, this is Einstein’s
04:21
theory, excuse me, Einstein’s equation. It relates energy and mass. And the cool thing
04:27
about it is when we convert hydrogen to helium we actually lose a little bit of mass. But
04:33
where does that mass go? That mass is converted to energy. And it’s the energy that’s giving
04:38
me the sun in this room right now. Okay. So the idea of atoms and molecules came from
04:44
the Greeks. And there was this guy named Democritus. And Democritus said that we could break down
04:49
all matter into small little tiny bits if we kept cutting it. And he coined that term
04:56
atomos which means to be uncuttable or undivisible. Now on the large scale elements, compounds,
05:06
all have different states of matter. And so states of matter are linked to the kinetic
05:12
energy of a molecule. And so if we look right here the ones that you’re probably familiar
05:16
with are going to be solids. And so we could think of this right now as like, ice in this
05:21
beaker. As we start to add energy to it, those water molecules will actually move around
05:27
and so that forms that next state which is going to be called a liquid. And if we get
05:30
enough energy to it, then this is going to be water boiling or these elements are boiling.
05:35
And so they’re eventually jumping off into a gas. So you’re probably familiar with those
05:39
three. So if we decrease the energy then we can go right back to a solid. Now the two
05:44
ones on here that I think are pretty cool are plasma. That’s when we get a gas really
05:49
excited and it starts to ionize. So it starts to give off electrons. Then we form something
05:54
called a plasma. Where have you seen a plasma before? You see that like in stars. But you
06:00
also see it like in fluorescent lights. So that’s a state of matter that you’re maybe
06:04
familiar with. But what happens when we really cool it down. When we really cool it down,
06:09
below a solid, we form something called Bose-Einstein, let me try that again, Bose-Einstein condensate.
06:18
And so it was predicted by these two scientists, Bose who was Indian if I remember, and Einstein
06:23
who was German. And what they predicted is that when you really cool stuff down towards
06:29
near absolute zero, weird stuff is going to take over. And so this really wasn’t tested
06:33
until 1995 when a couple of scientists at the University of Colorado actually were able
06:39
to use lasers to cool stuff down towards near absolute zero. And what they found was that
06:44
when you cool it down the Heisenburg Uncertainty Principle takes over. What does that mean?
06:50
Well when you slow down those atoms you know specifically where they are. And according
06:54
to Heisenburg’s Uncertainty Principle, when you know something is, where it is, you don’t
06:59
know anything about it’s momentum. So you get this weird spike where you don’t even
07:02
know where the atoms are. And that’s pretty wild. And that’s quantum theory. But again
07:08
there are five states of matter. Going from energy we go from plasma which has high high
07:12
energy all the way down to this Bose-Einstien condensate. But movement between those, we’ve
07:17
got terms for those. So what happens if we take a gas and turn it into a liquid? You’re
07:21
maybe familiar with that, we call that condensation. Whereas likewise if we vaporize it moves up
07:26
to gas. And so I love this diagram here because it shows all of those. But remember as we
07:30
increase the energy then we’re going to move up to different states of matter. How do we
07:35
measure matter? We could measure it directly. And so we could put it in, for example, a
07:39
graduated cylinder. And this is the meniscus. And you measure it along that point. We could
07:44
actually calculate it using volume. Or we could use displacement where you measure the
07:48
amount of water. You put an object inside it and then we measure how much it displaces
07:52
the water. So we could measure directly matter. But also remember that we can measure it indirectly.
07:59
How do we do that? Imagine if I take a cup of the earth. And let’s say that the earth
08:03
was homogeneous. If I take a small portion of the earth and figure out the mass of that
08:08
in grams for a specific volume, I could then, let me scratch that. If I take the mass of
08:16
a small bit and the volume of that, that’s going to equal the mass of a large volume.
08:22
And so for example, if I have a small volume, we’ll call that mass 1 and volume 1. And I
08:28
want to figure out how much the earth weighs, all I have to know is the volume of the earth
08:33
and then I can use the factor label method to figure out the mass of the earth. And so
08:39
sometimes in science we can’t measure really large things and really small things. And
08:43
so instead of measuring it directly using a scale or a graduated cylinder, we actually
08:48
have to resort to math. And we use ratios to figure out how much it weighs or how big
08:53
it is. And so I think that’s it. Where do we find matter? And we’ll do this in the next
08:59
few podcasts. We find it on the periodic table. And so the periodic table organizes all of
09:04
those pure substance elements that we have into an organizational chart that also shows
09:10
us properties of the matter. And so that’s just kind of an introduction to matter. And
09:15
I hope that’s helpful.