What is matter?... It’s anything that 1) takes up space and 2) has mass. What is energy?... Energy...
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Transcript of What is matter?... It’s anything that 1) takes up space and 2) has mass. What is energy?... Energy...
What is matter?... It’s anything that 1) takes up spaceand
2) has mass.
What is energy?... Energy is anything that causes a change.
So, an elephant is made of matter, since it definitely takes up space and has mass.
But air is also matter – the balloon takes up space, doesn’t it?... And if you put it on a scale, the air would weigh SOMETHING, wouldn’t it?...
That’s a change, right?...There’s all sorts of energy – heat
energy, chemical energy, electrical energy, mechanical energy….
(What causedthe change?...)
This is the periodic table.Each box represents one element.
So what’s an element?...
There’s a copy
of this in the
VERY BACK
of your book.
Check it out….
An element is something that is made of only one kind of atom.
So let’s take helium, for example (like in a balloon).
The element helium is only made of… helium atoms.
If you have a balloon full of helium, that’s millions of helium atoms.
You could also remove just one microscopic helium atom.
But it’s still just helium atoms.
So what’s an atom?....
ATOMS
These are both ways you may seeatoms drawn in books or online.
They’re TINY!
So you thought atoms are as small as it gets, right?Wrong.
Every atom is made up of negative charges called electrons.They’re the ones zooming around the outside.
It also has positive charges (protons)and uncharged particles (neutrons).Those are the ones in the center.
These are also ways to draw an atom….
The one on the left is a carbon atom.It has 6 electrons, 6 protons, and 6 neutrons.
Now flip to the back of your book. Find carbon in the period table. What number do you notice it is?....
Okay, now look at the atom on the right.It has 8 of everything (you can’t see all the protons and neutrons).
Look at the period table again. What element do you think this is?....
Get it?...
So what’s the difference between these two atoms?...
Now, these are all molecules.They can be drawn all these different ways, but…
…“molecule” just means a bunch of atoms put together.
Let’s look at a simple one.This is one molecule of water.
Remember, water is H20.So this means one atom of oxygen (the
red one) with two atoms of hydrogen (the white ones).
O
H H
What if we have two molecules of water?
It’s still just water. And you still couldn’t see it without a microscope.
It would take like a gajillion molecules of water to make this:
So is there a difference between a molecule and a compound?...
one hydrogen molecule + one oxygen molecule = one molecule of peroxide
the stuff in the
brown bottle
you put on cuts
and they fizz
BUT, the peroxide molecule also happens to be a compound.Why do you think that is?...
(Think about what a “compound” word is in Language Arts….)
just hydrogen just oxygen hydrogen AND oxygen
“Compound” means there’s at least two different elements that make up the molecule.
So…
Cl2 Two chlorine atoms – do they make a compound? No.Cl37 Thirty-seven chlorine atoms – do they make a compound? No.
NCl37 One nitrogen atom and thirty-seven chlorine atoms. Do they make a compound?YES!
H2 O2 H2O2
Mixtures are combinations of substances that DON’T become new things; they keep their
original properties.
A solution is a type of mixture, even though you at first may think it’s not. For example, what are the two things that mix to make sweat?...
The other kind of mixture is a suspension. Blood is an example of a suspension. What makes up blood?...
Next Topic…
This is a mixture – you can obviously see what its parts are.
But sweat is also a mixture – its parts are water and salt.
So is blood. It’s a mixture of red blood cells, white blood cells, plasma, and platelets. It you let it sit long enough
(like the picture on the left) it will separate into its parts.
solution
suspension
Want some more examples?...
Solution(the top of the bottle tastes the same as Gatorade from the bottom – the same proportion of ingredients throughout)
ItWAS
asuspension
The compounds that make up your body (and the bodies of every living thing) are
either organic or inorganic.
What’s the difference?...
Organic Vs. Inorganic
Well, first of all, “organic” means something different in the grocery store than it does in a chemistry lab.
In the grocery store, if you buy an organic apple, it means it wasn’t sprayed with pesticides.
If you buy organic milk, or organic hamburger, it means the cow wasn’t injected with hormones.
It basically means all-natural – and really expensive.
In science, the real meaning of organic is that it contains carbon (and the hydrogen that connects to it) and that it is, or once was, part of a living thing, or the product of a living thing.
The types of organic compounds that you have in your body are:
carbohydrates (sugars for short-term energy)
lipids (fats for long-term energy)
proteins (enzymes that make your body run properly)
nucleic acids (DNA and RNA for making you who you are)
like running a race tomorrow
like a bear needing fat to hibernate through winter
enzymes determine how fast or slow your body works inside
protein is why your
nails are so strong
The inorganic compounds are basically everything else.
The most important inorganic compound in your body?
Water!
Why?...
Water is important because…• Seeds/spores need it to reproduce and grow
• Chemical reactions in your body need take place in water(no chemical reactions, no life)
• Water helps transports things around your body(your blood is made of water, and travelsaround your body carrying stuff with it)
• Water is an insulator(It keeps you from getting too hot, or too cold – justlike those insulated lunch bags some of you have)
Penguins like it. (Just kidding –
look at the next slide….)
Water has some pretty cool properties….
For one, the atoms in water are strongly attracted to each other.
For another, water freezes from the top down.
Why do these two things matter?....
Ever see an insect walk on water?It’s basically because the water molecules are hanging onto
each other so tightly, an insect can’t fall through.
And, how do you think fish can make it throughthe winter in a “frozen” pond?...
http://www.youtube.com/watch?v=zpYatvnHkRI
http://www.youtube.com/watch?v=Dx4C-fkBik4
http://www.youtube.com/watch?v=V-cXzZt2iVk
http://www.youtube.com/watch?v=Rv41t68-fUI
You don’t have to watch the videos all the way through – just take a peek!(And they don’t need sound)
•What are 3 reasons water is important?
•Explain why there is a film on the top of water that makes it strong enough for an insect to walk on.
•Explain why water’s temperature takes a while to change. AND, why does it matter that water’s temperature changes slowly?
•Explain why water freezes from the top-down. AND, why does it matter that water freezes top-down?
(When you’re done, please raise your hand so Ms. Mankoski can check your answers.Then you can answer #1, 2, 3, and 5 on page 75.)