Oceanography: Properties Oceanography: Properties of Waterof Water

Density of WaterDensity of Water

• Density - Density - ________________________________________________________________________________________________________________________________________

• The equation for density is: D = The equation for density is: D = ____________

A substances mass to volume ratio or how many molecules are packed into a space.

m

v

• In most substances the density In most substances the density _______________ as the substance _______________ as the substance loses energy and the temperature loses energy and the temperature _______________. _______________.

• As the phase changes from a As the phase changes from a gasgas to to a a liquidliquid to a to a solid solid the density the density _______________._______________.

increases

decreases

increases

• _______________ and _______________ _______________ and _______________ water work this way. As they cool water work this way. As they cool the particles get closer together and the particles get closer together and the density _________________.the density _________________.

Gas liquid

increases

• _______________ water _______________ water (ice) is different. The (ice) is different. The density of ice is density of ice is actually __________ actually __________ than liquid water. than liquid water. This is because the This is because the structure of solid structure of solid water is a water is a ______________ that ______________ that spreads the spreads the molecules apart.molecules apart. (see page 492)(see page 492)

Solid

less

crystal lattice**The density of liquid water is 1 g/cm3 and the density of solid water is .92 g/cm3

• This is what This is what makes water so makes water so ______________ ______________ and what makes and what makes water water ______________ to ______________ to life on Earth.life on Earth.

different

important

Polarity of WaterPolarity of Water

• Water is a Water is a _______________ _______________ molecule, which molecule, which means that it has a means that it has a ________ charge and ________ charge and a ________ charge.a ________ charge.

oxygen

-

++

hydrogen

polar

+ positive

- negative

• The polarity allows The polarity allows water to create water to create ____________________ ____________________ bonds between bonds between individual molecules. individual molecules. This is what makes This is what makes water so water so _____________ and _____________ and why water has such a why water has such a high boiling point.high boiling point.

Hydrogen

sticky

• Water freezes at Water freezes at __________________

Water boils at Water boils at ______________________

• Liquid water exists Liquid water exists between __________between __________

• This is also what This is also what makes water so makes water so ______________ and ______________ and what makes water what makes water ______________ to life ______________ to life on Earth.on Earth.

0° C

100° C

0°-100° C

different

important

• Water’s _____________ also Water’s _____________ also

allows it to interact with allows it to interact with other substances called other substances called _________._________.

• ____________ increase the ____________ increase the density of water and density of water and change the temperatures at change the temperatures at which they freeze and boil.which they freeze and boil.

– When ions are dissolved in When ions are dissolved in water water

the boiling point the boiling point ___________________ ___________________ and the freezing point and the freezing point __________________ __________________

polarity

ions

ions

Increases (~100.3°)

Decreases (~-2°)

Why Is Water Different Than Why Is Water Different Than Most Other Substances?Most Other Substances?

1 2 3

0% 0%0%

1.1. It is the only polar It is the only polar molecule knownmolecule known

2.2. It expands when It expands when turning into a turning into a solidsolid

3.3. Its molecules get Its molecules get closer together closer together when it condenseswhen it condenses

Why Does Water Take So Much Why Does Water Take So Much Energy To Heat Up?Energy To Heat Up?

1 2 3 4

0% 0%0%0%

1.1. All of the molecules All of the molecules are bonded by are bonded by hydrogen bondshydrogen bonds

2.2. All of the molecules All of the molecules are bonded by are bonded by covalent bondscovalent bonds

3.3. It is very denseIt is very dense

4.4. It doesn’t – it heats It doesn’t – it heats up faster than landup faster than land

Why Do People Put Salt On Why Do People Put Salt On Streets When It Snows?Streets When It Snows?

1 2 3

0% 0%0%

1.1. It keeps the snow It keeps the snow from falling on the from falling on the streets streets

2.2. It makes the water on It makes the water on the streets freeze at a the streets freeze at a higher temperaturehigher temperature

3.3. It makes the water on It makes the water on the streets freeze at a the streets freeze at a lower temperaturelower temperature

Oceanography: Properties Oceanography: Properties of Ocean Waterof Ocean Water

Average Depth of Ocean vs. Average Elevation of Average Depth of Ocean vs. Average Elevation of LandLand

(Draw What You See…)(Draw What You See…)

Properties of Ocean WaterProperties of Ocean Water• _______ % of the Earth’s surface is _______ % of the Earth’s surface is

covered by oceans. The average covered by oceans. The average depth of the ocean is more than depth of the ocean is more than ____________ greater than the ____________ greater than the average elevation on land.average elevation on land.

• Five OceansFive Oceans1. 1. 2. 2. 3. 3. 4. 4. 5. 5.

> 70

four times

Pacific

Atlantic

Indian

Arctic

Southern (Antarctic)

Components of SeawaterComponents of SeawaterThe most common dissolved solids in seawater are:The most common dissolved solids in seawater are:

• Sodium ChlorideSodium Chloride

Magnesium Magnesium SulfateSulfate

Calcium SulfateCalcium Sulfate

NaNa++ ClCl--

MgMg2+2+ SOSO442-2-

CaCa2+2+ SOSO442-2-

Components of SeawaterComponents of SeawaterSome Some otherother ions that are found in seawater ions that are found in seawater

are:are:• Carbonate COCarbonate CO33- (builds shells)- (builds shells)

• Gold Gold Au+Au+• Uranium U+Uranium U+• Bromine Br-Bromine Br-

Components of SeawaterComponents of Seawater

• The ion that is most abundant in The ion that is most abundant in seawater is ______________seawater is ______________

• Carbonate ( ) is a way that Carbonate ( ) is a way that ____________ is stored in the ocean____________ is stored in the ocean

chloride, Cl-

COCO33--

carbon

Salinity of SeawaterSalinity of Seawater

• ____________ is a ____________ is a measurement of measurement of the dissolved the dissolved ____________ in sea ____________ in sea water.water.

CDT measures conductivity, temperature and depth

Salinity

Solids (salts)

Average Salinity of Average Salinity of SeawaterSeawaterThe average salinity of seawater is The average salinity of seawater is

_______________. _______________.

– This means that for every _______g of salts This means that for every _______g of salts there is ______g of water. there is ______g of water.

– _________: parts per thousand_________: parts per thousand

– _________: parts per hundred (percentage)_________: parts per hundred (percentage)

35 o/oo

35

1000

o/oo

o/o

What is the average What is the average percentagepercentage of dissolve solids of dissolve solids in the ocean?in the ocean?• (Part over whole)(Part over whole)

_______ x 100 = %_______ x 100 = %

• Because ______ % is an Because ______ % is an averageaverage it can vary: it can vary:

– _______________ stay close to the average salinity._______________ stay close to the average salinity.

– _________________ tend to vary above and below _________________ tend to vary above and below the average salinity.the average salinity.

35

1000

3.5

Deep Waters

Surface Waters

3.5

Examples of variations at the Examples of variations at the upper (surface) levels of waterupper (surface) levels of water

Examples of variations at the Examples of variations at the upper (surface) levels of waterupper (surface) levels of water

Examples of variations at the Examples of variations at the upper (surface) levels of waterupper (surface) levels of water

Measuring SalinityMeasuring Salinity

• The two ways to measure salinity:The two ways to measure salinity:

1. 1.

2. 2.

• Which way is more efficient? Which way is more efficient? _____________________. _____________________.

EvaporationConductivity

Conductivity

Measuring SalinityMeasuring Salinity

– It is important to measure salinity along It is important to measure salinity along with ________________ in order to track with ________________ in order to track _________________. _________________.

– Water does not stay in one place it will Water does not stay in one place it will move due to changes in _______________.move due to changes in _______________.

temperature

ocean currents

density

Changes in DensityChanges in Density

TemperatureTemperature DensityDensity

WARMWARM LOWLOW

COLDCOLD HIGHHIGH

Changes in DensityChanges in Density

SalinitySalinity DensityDensity

Low (not a lot of Low (not a lot of salts)salts)

LOWLOW

High (a lot of salts)High (a lot of salts) HIGHHIGH

What Percentage Of The What Percentage Of The Earth’s Surface Is Ocean?Earth’s Surface Is Ocean?

1 2 3 4 5 6

0% 0% 0%0%0%0%

1.1. 70%70%

2.2. 30%30%

3.3. 90%90%

4.4. 50%50%

5.5. 1%1%

6.6. 100%100%

What Is The Most Abundant What Is The Most Abundant Dissolved Solid In Seawater?Dissolved Solid In Seawater?

1 2 3 4

0% 0%0%0%

1.1. GoldGold

2.2. UraniumUranium

3.3. Sodium Sodium ChlorideChloride

4.4. Magnesium Magnesium SulfateSulfate

What Is The Average Salinity What Is The Average Salinity Of The Oceans?Of The Oceans?

1 2 3 4 5

0% 0% 0%0%0%

1.1. 3.5%3.5%

2.2. 35 parts per 35 parts per 10001000

3.3. 35%35%

4.4. 1 and 21 and 2

5.5. 1, 2, and 31, 2, and 3

Which Part Of The Ocean Has A Which Part Of The Ocean Has A More Stable Salinity?More Stable Salinity?

1 2

0%0%

1.1. Shallow WaterShallow Water

2.2. Deep WaterDeep Water

What Drives Surface What Drives Surface Currents?Currents?

1 2 3

0% 0%0%

1.1. Fish SwimmingFish Swimming

2.2. Differences In Differences In Density Due To Density Due To Salinity and Salinity and TemperatureTemperature

3.3. WindWind

What Drives Density What Drives Density Currents?Currents?

1 2 3

0% 0%0%

1.1. Fish SwimmingFish Swimming

2.2. Differences In Differences In Density Due To Density Due To Salinity and Salinity and TemperatureTemperature

3.3. WindWind

What Is The Least Dense What Is The Least Dense Water?Water?

1 2 3 4 5 6

0% 0% 0%0%0%0%

1.1. Hot, Fresh WaterHot, Fresh Water2.2. Cold, Fresh WaterCold, Fresh Water3.3. Room Temperature Room Temperature

Fresh WaterFresh Water4.4. Room Temperature Room Temperature

Salt WaterSalt Water5.5. Cold, Salty WaterCold, Salty Water6.6. Hot, Salty WaterHot, Salty Water

What Is The Most Dense What Is The Most Dense Water?Water?

1 2 3 4 5 6

0% 0% 0%0%0%0%

1.1. Hot, Fresh WaterHot, Fresh Water2.2. Cold, Fresh WaterCold, Fresh Water3.3. Room Temperature Room Temperature

Fresh WaterFresh Water4.4. Room Temperature Room Temperature

Salt WaterSalt Water5.5. Cold, Salty WaterCold, Salty Water6.6. Hot, Salty WaterHot, Salty Water

DemonstrationDemonstration

• Draw the test tube and label the Draw the test tube and label the layers I put in.layers I put in.