MathScience Innovation Center 2010 Misbehaving Molecules— Atoms Alive Mrs. Hobbs MathScience Innovation Center.

MathScience Innovation Center 2010

Misbehaving Molecules—Atoms Alive

Mrs. Hobbs

MathScience Innovation Center


What is going on with those molecules?

Are they behaving badly or just doing what molecules do?

Let’s investigate.


Water--our first molecule

We will use two teams to do our water investigation. Each team needs three students.


Water Investigation

Investigators:

find a cup and fill it half full of water

then add your materials


Add these materials:

a

aa

a

aa

a

aa

Cup 1 three drops of oil Stir 10 times

Cup 2 one small scoop of salt

Stir 10 times

Cup 3 one ice cube

Stir 10 times


What happened?

Cup 1

The oil sits on top of the water and will not mix with it.

Cup 2

The salt mixes with the water and disappears.

Cup 3

The ice cube floats on top of the water.


Were those molecules misbehaving?

Why won’t the water mix with the oil?

Can’t they be friends?


What happened?

• Why does the salt disappear?

• Is it like a ghost? Can we make come back? How?


Are the molecules misbehaving?

Why doesn’t the ice sink?

Solids are supposed to be denser than liquids.


What do the new materials do?Sample # What do you think it will do in

water?What happened?

Why?

1

2

3 You may stir it.

4

5

You may fold it.


Sample # What do you think it will do in water?

What happened? Why?

1 It mixed with water and made it a bit green.

It dissolves—it is more like water than oil.

2 It settled to the bottom and made a sludge.

It dissolves—it is more like water than oil.

3 You may stir it.

It settles to the bottom and then dissolves.

It disappears like salt but does not look like

salt.

4 It goes straight to the bottom. It is a solid with high density.

5 You may fold it.

It floats until it is folded very small. At first it floats because it is flat but then sinks.

What do the new materials do?


Molecules come big and small

This molecule is monatomic.

This molecule is

diatomic.


Could these be molecules?

YES1.

2.

3.

4.YES

YES

YES


What shape are molecules?

Some are linear

Some are bent

Some are planar and trigonal

Some are pyramidal

Some are tetrahedral


Reacting Molecules

Element molecule Element molecule

Compound molecules


Computer pictures tell a molecule story


ChemSketch


We can draw molecule images with ChemSketch


Choose an element:

Carbon is the default choice.


Click on the white board to drop a molecule and then drag to add more parts.


Now, click on the red and white arrow to “Clean Structure”


You may need to erase.


Now you try it– make this structure.

CH3

CH3

Every point has a carbon so we have 6 carbon atoms.


If you want to name your new structure:

Click on this icon at the upper right of the screen.


So your new structure is called:

CH3

CH3

hexane

hexane


What does that name mean?

hex means 6 carbons like a hexagon has six sides

ane means that it has all single bonds


Can you draw this one?

CH3 CH3


Here is its name:

CH3 CH3

propane


Click on the icon at the top right

to make 3 dimensional pictures


Stick model


Now try some of the other versions:

This is ball and stick.


Add the hydrogen atoms


This is the space filling model


Click “View”, “Label All”


Click “Tools”, “Auto Add Frames”

You can make your own molecule movie.


Once completed these images can be copied and pasted to documents


Draw one water molecule Click on oxygen and drop it on your white

board.

Now make it 3 dimensional.

Draw it on your chart in the place for H_ O_


What does water look like?

1. H-O-H

2. O-H-H

3. Or something else?


Molecule Formulas Chart

Make each molecule on your chart and then draw it.

Once you have finished identify the shapes of each one.

Then create molecules of your choice and draw them too.


Chart 2 Everyday Molecules

For those who finish early there are more molecules to draw.


Back to water

We know its formula.

What else do we know from our experiment?

What did it do with oil?

What did it do with salt?

What did it do with ice?


Water and Oil

Let’s try out some models.

What shape is the water?


Water and Salt

How do the water molecules act towards each other?

What does that tell us?


Water and Ice

Put your six models in the box and shake.

What shape do you get?

Why does ice float?


Do you recognize these ice clusters?


What do we know about water• Water molecules have a bent shape.• Molecule shapes and formulas are found

in patterns.• The periodic table helps us to predict

those shapes and formulas.• Ice forms 6 sided clusters.


Do you know these molecules ?

MathScience Innovation Center 2010 Misbehaving Molecules— Atoms Alive Mrs. Hobbs MathScience Innovation Center.

Documents

chemsketch slide

tetrahedral slide

molecule story slide

water mix

times cup

molecule images

small scoop of salt

drops of oil