Water’s Unique Property Lab. Experiment #1: What is cohesion? -waters attraction to other water...

Water’s Unique Property Lab

Experiment #1:

What is cohesion?-waters

attraction to other water molecules

Cohesion: the attraction between like molecules. (one water molecule to another water molecule.

- Due to the fact that water is a polar molecule and opposites attract.

Experiment #5:

What is surface tension?

A property of liquid surfaces that causes the surface layer to behave like a thin elastic 'skin'.

Molecules in a liquid have attractive forces that hold them together.

Molecules on the surface are attracted to molecules from all sides and below, but not from above. ...

Experiment #3:

Water Alcohol

Density: Mass/Volume

Water in it’s solid form is less dense than its liquid form.

But why?

Again, WHY ?When frozen, the water

molecules slow down and due to their polarity they will line themselves up + to – end thus taking up more volume and lowering it’s density.

O

H H

- +

..

O-

H H+H

HH

H

O

O

SolidLiquid

Likes dissolve likes

Water is polar so it will dissolve any other substance that is polar

A polar molecule has one + and one – end

Did salt dissolve in water?

Yes it did

Why?Salt is NaCl Na+1 Cl-1 Since salt has a + and – end it is polar

Did sugar dissolve in water?

Yes it didWhy?

Sugar is a polar molecule

Did oil dissolve in water?

NO

Why?

water is polaroil is not polar, it is

nonpolar

Did powder soap dissolve in water?

NO

Why?

water is polarsoap is not polar, it is

nonpolar

Why? Grease/oil is nonpolar and soap is nonpolar

What occurred?

Why did this occur?

Due to cohesion and adhesion

Adhesion:

Waters attraction to other substancesWater attracted to the string

Cohesion:

Water attracted to other water molecules