>> Welcome to compounds, part zero.
In this video lecture, we're going to look
at how we can make friends with ions
because they're really essential to success
in pretty much any chemistry course,
especially at the introductory level.
So let's get started.
All right.
So what I've done here on this page is I have the top
of our class ion list.
And if you haven't taken time to do this,
I think this could be really helpful.
We want to look for the patterns.
Now the tricky part will be to try to squeeze it all --
Well, you'll just have to look at the top, all right.
So when we look at our ion list and we look right here,
right, what do we notice?
We'll just slide up and down, right.
So here, all of these plus one ions are all in group one.
And so, you're always going to have access to a periodic table.
So if you see these elements and you're asked
about their ionic form, because they're in the first column,
we know they're going to be plus one.
Now, if we go to the second, if we look here, right,
there is the bulk of our plus two cations.
And what we can see is these are all the alkaline earth metals,
right.
So they're plus two.
So once again, just based off the position
on the periodic table, we've got them memorized.
Now let's go a little bit further.
Let's see here, our plus threes, okay.
So there's our buddy aluminum, right.
Aluminum is interesting because it is the only element that's
touching the stair step line that is a metal.
So there's our plus three.
And then, I'm not sure if you've noticed this or not,
but that's part of the reason for the video.
If we look here, we can see silver and zinc.
What's strange about their names?
Notice that here is -- Let's go up here.
Let's see.
There's our buddy silver and there's zinc, right.
So this is where we have the transition metals
with variable positive charge.
But notice that the zinc and the silver don't have a
Roman numeral.
These have fixed charge.
So they're exceptions to the rule, all right.
So silver and zinc don't have Roman numerals,
even though we might expect it because they're tried-and-true.
Silver is always going to be plus one,
and zinc's always going to be plus two.
But for the rest of these, right -- So when we look at copper,
whoops, yeah, all of these, right,
all of these elements here, these transition metals
and the plus threes and the plus four are higher.
We see that they primarily are occurring here
in the transition metals.
And then we've also included tin and lead.
Where are you?
Okay, right there.
All right.
So tin and lead also have variable charge.
So just take advantage with the cations of looking
at the position and the column number and that will help you
to memorize and remembering if there is variable charge.
We've got to have that Roman numeral.
If you were wondering in grade school why your teacher was
teaching you about Roman numerals,
it was for this class right here, chemistry.
Okay. Now, we'll go through the same process with the anions.
All right.
So just like before, right, if we look here, right,
here's our halogens minus one, right,
and there's our buddy hydride minus one.
So those are all right here.
So simply based off the position
on the periodic table, we know the charge.
And then, right, oxide and sulfide right there, minus two.
Here you go.
And nitride and phosphide minus three.
There we go, okay.
Now notice the ides, right.
So all of these ions are monatomic.
There's only one, right.
So when you see that "ide" suffix, you can think of it
as I'd rather be alone, okay.
So that will help.
Now, I know -- So there is hydroxide and cyanide.
Those are two common ones.
The I'd rather be alone doesn't work for those, but it does work
for the other ones, right.
So if we look at phosphide versus phosphate, right,
you can think when you see the "ate,"
some students say it's really helpful to think that the
"ate" is mated with oxygen.
All right.
Little patterns like that can be helpful.
So that still leaves us with quite a few polyatomic anions.
These are going to take a little work to memorize,
but on the next page, I'm going to show you a few more tricks
to help you make friends with these polyatomic anions.
I do want to reassure you
that this is the shortest ion list on the planet.
It's really been distilled
down to the most biologically relevant,
and so these are really going to be essential for you to memorize
to be successful in the course.
I wanted to show you one quick example before we move on.
Let's look here.
Let's see.
Yeah, so let's look at carbonate, right.
So there's carbonate right there, all right.
And now let's look.
Here's bicarbonate.
All right.
So what's -- Here's carbonate and bicarbonate.
So notice the difference, right.
The difference is this one hydrogen, all right.
So positive and negative comes together.
So think about the H plus difference.
So it can also simplify memorizing the ions
if we memorize carbonate as minus two, all right.
So then when we look at bicarbonate, right,
we brought together an H plus
with a carbonate two minus, right.
So when we have the plus one and the minus two,
that's how we get the net minus one.
Whoops, all right.
So bicarbonate is simply a hydrogen ion and a carbonate.
When those two come together, they form the bicarbonate.
And so, that can help to minimize as well because we see
that also, like sulfate and bisulfate, right,
and phosphate biphosphate or hydrogen phosphate,
so thinking about the hydrogen ion as the plus one.
So as you're memorizing these, I would focus on the phosphate,
the carbonate, and the sulfate.
And then once you get those down, you can puzzle
through the rest, and that will make it a little simpler.
Okay. And then a little bit more help on these polyatomic anions
because they really do appreciate
that they are the hardest work, the most difficult to memorize.
So let's look at those a little more closely.
And here's a trick, all right.
So if you want to, you can just write,
Nick the camel ate supper in Phoenix.
And then there's a little trick
to help you memorize those base polyatomic anions, right.
So the number of consonants tells us the number
of nitrogen atoms, right.
So the n tells us this is nitrate, all right.
And if we look here, there is one, two, three consonants.
So that means there would be three oxygen atoms.
And then the number of vowels gives us the charge.
So there's one vowel, so that means we would have a minus
one charge.
Let's practice this a couple more times, all right.
So the C, that would be for carbonate.
The number of consonants, one, two, three.
There's three consonants.
That means there's three oxygen atoms.
The number of vowels.
Now we have one, two vowels.
So that's a minus two, all right.
So Nick the camel ate supper, right.
So the supper, that'll be our sulfate.
So there's our sulfur.
The number of consonants equals the number of oxygen atoms, one,
two, three, four, four oxygen atoms.
And then the number of vowels is the charge.
So there's one, two vowels, minus two.
And then last but not least, all right, Phoenix.
That would be for phosphate.
So there's our phosphorus, one, two, three, four.
once again, four consonants, so four oxygen atoms.
And then this time, one, two, three vowels,
all coming together to make minus three.
So if you need to, just quickly, right, at the top of your paper,
you know, before a quiz or exam, write Nick the camel ate supper
in Phoenix, and then you can fill it from there.
Ultimately, you're going to practice enough,
you're not going to need the trick.
But if this helps you get started,
then please take advantage of it.
There's one last polyatomic ion
that needs our attention, and that's acetate.
Acetate has huge applications when we get to biochemistry.
And so, it can seem a little ignored or not
so important initially, but it will be.
And for our basic knowledge quizzes, you'll see it a lot
because it's very important.
So here's a prefix, acet.
We've been focusing on the suffixes, but here,
when we see acet, that tells us that we have a carbon
with three hydrogens present.
And down the road, we're going
to learn this is a methyl group, but not for a while.
That's a sneak preview, okay.
So when we look at the two -- So when you look on your ion list,
it's going to show two chemical formulas for acetate.
This is the one that will be the most useful to us, CH3.
There's our CH3 group and then the CO2, all right.
Or you can see it written like this.
So notice that they're the same chemical formula, right.
We have two carbons, three hydrogens into oxygen.
What makes this first formula more helpful is it actually
gives us the structure, all right.
This one only gives the formula, okay.
So I want to show you exactly what acetate looks like.
And this is a little bit ahead, but, you know,
it's a sneak preview and I think it's going to help, right.
So the two carbons are bonded together because we know
that that acet, right.
There's our acet right there.
There's our CH3 group, okay.
And then, here we go, right.
There is out eight.
All right.
So the negative charge goes here.
Just to keep it pretty, I'll put the lone pairs on.
There we go.
Right. So this is the same chemical formula
for the same structure.
These are both acetate.
I really encourage you to get comfortable
with the structural formula for acetate.
It's going to be an investment in your future
to help you out down the road.
Oh, and so now, I wanted to talk a little bit
about the ion flashcards.
So as you're doing your ion flashcards,
you'll want to just use like three-by-five cards, right.
So you put the name on one side, right.
So when you see the name acetate,
your brain should see the chemical formula CH3CO2 minus.
So you've had homework to make your ion flashcards,
and this is how you want to do them, right.
So no hints.
Sometimes students want to put hints on the name side,
but that's not going to work.
You got to have everything from the chemical formula side needs
to be in your brain and vice versa.
So here's a sample of how to do your ion flashcards.
So that wraps up this video.
Now would be a great time to take a few minutes
to do the post-video practice problems.