- [Voiceover] In this chapter we're looking at
the chemistry.
So first off, what is chemistry?
In the most basic sense chemistry is the study of matter.
It's looking at the different parts and pieces around us.
What is matter?
Matter is anything that occupies space
and that has some mass to it.
Now matter is always composed of elements.
So you look around, and you say OK, what's matter?
(mumbling) screen you're looking at,
or the tablet screen you're on.
Can look at any pens or pencils.
They're made of matter.
Floor, walls, ceilings, plants, boxes, textbooks.
Anything is made of matter if it occupies space.
It can occupy a lot of space like the entire office complex,
or it can occupy a tiny minuscule amount of space.
Think of an ant, or even go smaller than that.
So these elements that make up the matter,
these elements are the simplest form.
They cannot be broken down.
They cannot be broken into smaller elements.
The element is the most basic system there is.
Gold is an element.
Silver is an element.
Copper is an element.
Oxygen is an element.
Hydrogen is an element.
So those are all pretty simple, pretty basic, sure.
Water.
Water is not an element.
Water is H2O.
It's hydrogen and oxygen together.
It takes two elements, hydrogen and oxygen,
to make up water.
So elements, no matter how small of particles you
break them into, are always the same thing.
And all these elements are listed throughout
the periodic table.
So here's an example of the periodic table.
Now as you look across it you'll notice a lot of
letters and numbers.
What you're looking at is the smallest and simplest
of all elements are towards the top.
Number one, that's gonna be your simplest, hydrogen.
As you go across, your number two is helium,
three is lithium, they keep going on.
Where it gets important for human beings is number six,
which is C, or carbon.
Number seven, N, which is nitrogen.
Eight, which is O, which is oxygen.
Those are some pretty basic and pretty simple components.
And you notice because they're in the lighter shaded tone
they're non-metals.
Most of these periodic elements, the darker shaded tone,
which are metals, you can see are the majority of them.
As you go down towards the bottom of the chart
the numbers get larger, and odds are you probably haven't
heard of a lot of these abbreviations or have any idea
about some of these things.
They're more on the rare side.
They're not really seen very often.
So the most common forms are up higher in the chart.
For instance, number 26, ethene, that's simply iron.
Twenty-eight, NI, nickel.
So you can go through, and a lot of these you probably
have heard before,
just maybe not sure of all of the abbreviations yet.
But for our purposes we're looking at the idea of
what this chart is telling us.
The first row across only has two elements.
That means the outer ring of electrons
can only hold two electrons.
You're saying electrons, what are those?
Electrons are negatively charged parts of an atom.
They usually circle around the element.
Well, if you go into the second row, you can see there's
a total of eight elements across.
That means the outer shell for these is gonna have
eight electrons possible.
You're saying well, how do you know which one is which?
Well, the first column, which is number three LI,
has one electron in the outer shell.
Second column, number four, BE, has two electrons.
Third column, number five, B, has three electrons.
Fourth column, number six, C for carbon,
is gonna have four electrons.
Five is found for number seven, nitrogen.
There's six electrons in the outer shell
for eight, oxygen.
Seven electrons in the outer shell for nine, flourine.
And a total of eight electrons in the outer shell
for NE, or neon.
So now we have basically going down tells you how many
electrons are in the outer shell.
Now atoms are gonna consist of several different parts.
They're gonna consist of their nucleus,
which is the central core.
It's what's really the very center or heart of an atom.
Then they have the shell around it.
The shell, as I mentioned, contains electrons.
Well, let's start with the nucleus.
You can find protons inside the nucleus.
Protons are small particles that will have a slight
positive charge, and they do have mass.
You can actually weigh a proton.
Now it's not gonna weigh very much,
but you could actually weigh it and have mass behind it.
The second component of the nucleus are neutrons.
Now neutrons do not have a charge.
Think of neutrons as neutral, and neutrons also have mass.
That means both protons and neutrons give weight to an atom,
or give mass to an atom.
While the electrons that are found in the shell or found
kind of circling around the outside of the nucleus,
they're gonna have a negative charge.
But really, even though they have a negative charge,
there's pretty much no mass found.
There's no discernible mass.
So we have our protons, neutrons, electrons
make up an atom.
Now majority of the atoms will have some protons,
some neutrons and some electrons.
But some of the smallest do not have all three components.
So you can think of it this way.
Protons, P, positive, proton positive.
Neutrons, neutral, neutrons neutral.
Electrons, though, gotta remember that one (mumbling).
Electrons, negative.
Electrons have a negative charge.
Up top here we see hydrogen.
Now hydrogen is the simplest of all the elements.
It's the first in the periodic table.
It has one proton and one electron.
That's as simple as it will get.
Notice how the electron is out in that blue sphere.
You can find the electron any place out there.
It's constantly bouncing around, moving all around.
The proton though, will always be the nucleus.
The proton can be the center anchor or core of the element.
As you get more complex moving down to B, oxygen.
In oxygen you can see you have eight protons
and eight neutrons.
But it also says you have eight electrons in two shells.
What this means, if you remember back to the periodic table,
oxygen is found in the second row.
That means there is one row up top which has the inner shell
maximum of two electrons.
But oxygen's in the second row,
which contains a second shell that means.
If you're looking at the electrons, the little negative
symbols in the two red spheres, you can see the smaller,
inner sphere has two negative symbols.
That means it has two electrons floating around it.
But the larger outer red sphere is going to have
six electrons.
Now we know that it could take up to eight,
but it only contains six.
And we can know that it should be six
by looking at the periodic table.
If you look at the periodic table, you'll notice that oxygen
is in the sixth column in that second row.
So we have a total of electrons, two in the first column,
then six in the outer shell.
Let's go to the very bottom, sodium, the yellow.
You can see that sodium has three yellow spheres around it.
That's symbolizing the three different shells of electrons.
We know sodium must have three shells because when we
look at the periodic table,
sodium is in the third row of elements.
So that means the first row we know contains two electrons
in the first shell, the smallest sphere.
Then the second row can max out at eight electrons,
which sodium has eight electrons in that second shell.
And the third shell, the outer shell, only has one electron.
Well, we know it has one because sodium is in the first
column in the third row.
So as you build these spheres, first, second, third shell,
each one is gonna fill up based on how many potential
electrons it can hold.
First shell, max of two.
Second shell, max of eight.
Third shell, max of eight.
Now if you go down the chart, the periodic table,
there are more shells beyond.
We're not touching those, don't worry.
We're looking at the basic first three rows.
So you can have a two-eight-eight pattern as the maximum.
Look at these atomic symbols.
They're usually one or two letters.
Na stands for sodium.
O stands for oxygen.
We saw H stands for hydrogen.
We saw C stands for carbon.
So there are a lot of different letter abbreviations
to symbolize all the different atoms.
The atomic number that you see is the number of
protons present.
So if you looked at that periodic table,
hydrogen was atomic number one, had one proton.
Helium is atomic number two, has two protons.
Refer back to the previous page, we said oxygen
had eight protons.
That's because it has the atomic number eight.
The atomic mass, well it's usually pretty close to
the number of protons and neutrons.
The reason it's only protons and neutrons remember,
is electrons really don't have any mass.
The only mass is found by the protons,
which are a positive charge,
and neutrons, which are neutral.
So all of these different atoms,
they're on your body, they're coming together,
they're mixing and matching,
they're helping form energy because we have energy
to go about our daily lives.
We have different forms of energy.
One type is potential energy.
That's your stored energy, the energy that you have
ability to do action or to do work.
Kinetic energy, energy in motion.
It's what happens when you take your potential energy,
you convert it into a movement.
So you're taking potential energy and converting it
into kinetic energy.
So it's the energy in motion, the ability to do work.
So you can take that potential energy,
transform it into kinetic.
You can kind of think of it this way.
If you were to climb up a flight of stairs,
would you be storing energy as you went up every stair?
Sure, you're going against gravity, storing energy.
Now if you took a basketball or any sports ball up to
the second story with you,
if you just let it go over the edge of the stairs,
would it go back down?
Of course, because the potential energy is being converted
into kinetic energy as your movements, pulling down.
Kind of think of it as this example in the book.
Potential energy is found in the chemical bonds of these
energy storing molecules in the diver.
Well, once he starts to perform his dive,
that potential energy is converted to kinetic.
He uses the energy that's been stored to create a movement
to cause the diving action.
So potential stored, kinetic, the energy of movement.