Water

Liquid water

molecules are a bit scattered, but still holds a bit of their form

Ice

molecules are organized

A mixture forms when one substance, the _____, dissolves into the solvent. The property that describes the "dissolving" ability of water is its _____.

solute; solubility

_____ _____ describes the capacity of water to hold on to its heat.

specific heat

_________ _________ describes how the surface of water acts like a skin and seals up quickly after being disturbed.

surface tension

Why is water like a magnet?

they are opposites so they attract; the positive part (hydrogen) is attracted to the negative part (oxygen) of a neighboring molecule

Water is called the ______ _______ because of its ability to dissolve so many different substances.

universal solvent

In the 1st flat portion of the graph (b), describe what is happening as energy is added.

As energy is added, it doesn't go to speeding up the molecules. (temp is constant). Instead, the energy begins moving the molecules further apart=phase change (solid to liquid)

In the 2nd flat portion of the graph (d), describe what is happening as energy is added.

As energy is added, it doesn't speed the molecules up (temp is constant). Instead, it pushes the H20 molecules further apart; some gain enough energy to escape into the air. Liquid to gas

In the 2nd rising portion of the graph (c), describe what is happening as energy is added.

As energy is added, the liquid molecules are moving faster. This is why the temp is increasing. Still in liquid phase the entire time.

In the first rising portion of the graph (a), describe what is happening as energy is added. Discuss this in terms of the molecules.

As energy is added, the solid molecules are vibrating faster (moving more). They are still compact together.

What is the difference between endothermic and exothermic?

Endothermic- heat being added Exothermic- less heat is being added

Water contains half as many hydrogen atoms as oxygen atoms.

False

Liquid to Solid

Freezing

Condensation

Gas to Liquid

The temperature of a road in the winter is 32 degrees Fahrenheit. Your friend is driving you to school and says that it is 34 degrees Fahrenheit outside, so there won't be ice on the road. Is your friend correct? Why or why not?

No; The road is 32 degrees Fahrenheit so there is a phase change occurring on that road. The road does have some liquid water on it, bu it has some solid ice too.

We have a sample of water at 100 degrees Celsius. When will the temperature start increasing again?

Once every single H2O molecule has made the transition to gas phase.

Sublimation

Sold to Gas

Melting

Solid to Liquid

In the 3rd rising portion of the graph (e), describe what is happening as energy is added.

The gas molecules begin moving faster & temp is increasing again.

Water is a polar molecule which means it has slightly charged ends. This unique molecule is why it has so many unique properties.

True

Water is made up of 2 atoms of hydrogen & 1 atom of oxygen to form a molecule.

True

______ Is the property of water that causes water molecules to "stick" to other substances.

adhesion

What is the biological significance of bodies of water when it is frozen?

bodies of water don't freeze through in the winter. The water that does does freeze, floats insulating the water & wildlife below it.

What is a phase change?

going from one of the phases of matter to another -the REVERSIBLE +solid to liquid liquid to solid + liquid to gas gas to liquid

_______ describes how water moves against gravity & can travel up a plants roots into its stem and leaves.

transpiration

Why does water both melt and freeze at 0 degrees Celsius? What determines whether something is melting or freezing?

0 degrees Celsius is the temp where the energy added/ removed goes toward the phase change. If you're removing energy, you are freezing it. If you're adding energy, you are melting it.

Gas to Solid

Deposition

Does it change the identity of the molecules involved?

No; same chemical formula Ice- H20 Liquid-H20 Ice-H20

The chemical formula for water is H20.

True

______ is the property of water that causes water molecules to "stick" to each other.

cohesion

Liquid to Gas

evaporization

Water is unique, in that it _____ when frozen.

expands

____ water dissolves things faster than ____ water.

hot; cold

What is the name of the weak attractive forces that hold water molecules together?

hydrogen bonds

Water has a density of 1 g/cm cube. Many substances will float in water. If a substance floats it is due to the fact that it has a ____ density than water.

lower

What is specific heat's biological significance?

makes water resistant to temp change. Therefore, in the summer our bodies resist temp change so we don't overheat in extreme heat.

gas

molecules move fast which results to being really disorganized, and being everywhere

A molecule that has electrically charged ends is called a _______ molecule.

polar

Water's specific heat makes large bodies of water cool down ____ than the nearby land.

slower