Layering Liquids

Today you are going to:

layer 4 unknown liquidsin a straw

so that none of the liquids mixes with

another

Base: potato slice Straw: 45° angle Pipet: slowly add liquid

Class Discussion:

What were the results?

Glycerin

Salt water

Fresh water

Isopropyl alcohol

Clean up

Carefully place potato basein trash container…

dropping it will splash the food coloring out of the straws!

Class Discussion

Why did the liquids layer that way?

This beaker is filled with marbles. Can I fit

anymore into this space?

Will this

salt fit in the beaker

?

Now there is more stuff in

here than before.

Can I add anything more to

this space?

This is the same

amount of space as when I started

with just the

marbles, but now

there is a LOT more

stuff in here.

Jar is filled with water. It has dissolved some of the sugar at the top of the beaker.

Scientists have a word to describe how much stuff is

in a certain amount of space ~

density

density = stuff space

These terms don’t seem “official.”

In math, what is space called?

These terms don’t seem “official.”

In math, what is space called?

density = stuff space

volume

density = stuff =

space volume

What do we call stuff

in science?

What do we call stuff

in science?

density = stuff =

space volume

Matter which has massmassMatter which has massmass

density = stuff = mass

space volume

density = mass volume

Glycerin

Salt water

Fresh water

Isopropyl alcohol

Salt water is more dense that fresh water, because in the same volume (amount) there are dissolved salts and other substances along with the water molecules. This means

there is more mass in the same volume ~ making salt water more dense.