objectives: › describe the amount of fresh water on earth › relate the structure of water...

Fresh WaterChapter 14

Section 1 Water and Its Properties

Objectives:› Describe the amount of fresh water

on earth› Relate the structure of water

molecules to the physical and chemical properties of water

› Explain why living things need water› Generalize about the role of energy

in the water cycle

Skills Warm-up

Down the Drain› How much water do you use in a

day?› Use the following estimates in your

calculations: Toilet – 20L/flush Glass of water – 0.25L Faucet – 15L/min 5-minute shower – 75L

Earth’s Fresh Water Earth is the water

planet – ________ of surface covered by water

Total Water:› ________ salt water› ________ fresh water in

glaciers/ice caps› ________ water is

underground› _____ is in atmosphere› Whatever is left -

surface fresh water

Put it in Perspective

Imagine ___________ of soda – represents all of earth’s water

Now imagine _______ of soda – represents the amount of usable fresh water

We must protect and conserve !

Properties of Water 3 Phases of Matter ________ – has its own

shape because molecules are held together rigidly

_______ – takes shape of container because molecules not held together as closely

____ – fills its container because molecules not held together

Properties of Water

Water is the only compound that occurs in all 3 ______ ___ _______ at ________ earth temperatures

Ice covered lake› Ice is water’s solid

phase› Water underneath is

the liquid phase› Water vapor above

ice is the gas phase

Water Molecule

Water’s chemical formula is _______

What does that mean?

Water is a _________ molecule – the hydrogen atoms have a slight __________ charge and the oxygen a slight __________ charge

Water Molecule

Since opposites attract:

The ___________ atoms from one water molecule are

Attracted to the __________ atoms from other water molecules

They “stick” together through ___________ __________

Physical Properties of Water

Water gains and loses heat energy _________ compared to other compounds

Heat is the energy of ___________ molecules

It takes ________ energy to separate polar water molecules and get them moving

Water also ________ ______

Physical Properties of Water Normally a

material’s solid phase is _______ than its liquid phase

But, water’s solid phase is ____ _______

This is because water’s polar molecules can’t get too close together

Like charges _______ That is why ice

______ on water

Physical Properties of Water

Water has ________ _______ – its surface is a skin-like layer

This occurs because water molecules _________ each other

Gives water droplets a __________ shape

Also causes light objects to ________

Chemical Properties of Water Water is called the

_______________________ It can dissolve many

other _____ substances Think of all the things

you drink (milk, lemonade, soda) that are mixtures of other things in water

This is also due to water molecules’ ______ – they attract other things and keep them in solution

Activity

Water Lab

Water Cycle The water cycle is a

_________________ of evaporation and condensation that controls the distribution of the earth's water as it:

____________ from bodies of water

____________ ____________ ____________ to those

bodies of water

Water Cycle _____________ – water

vapor condenses into liquid water

_____________ – liquid water is heated by sun’s energy to form water vapor

_____________ – Water falls as rain, hail, sleet, or snow

________ – when water cannot soak into the ground – gravity pulls it downhill

Water and Living Things

_________ is essential for all living things

About _______ of your body weight is from water

You can survive ______ without food than without water› 3-5 days without

water› Several weeks

without food

Water and Living Things

We take in water by ________ and ________

We release water in _____________, _____________, _____________, etc.

Water keeps us cool on hot days – heat energy from your hot skin evaporates watery sweat, cooling you off

Water and Living Things ______ use water, along

with carbon dioxide and light from the sun for ____________________

_____________ – process by which water move up through a plant eventually exiting through tiny __________ in their leaves

_______ __________ of water return to the atmosphere by transpiration

Your Water Use On average, each person in U.S. uses

__________ of water/day – not including indirect uses

Your Water Use

If you include all indirect water uses – the average consumption is over ___________________

Indirect water use can include:› 200,000L to ____________› 800L to ________________› 500L to ________________› 4,000L to ______________

Your Water Use

Where does fresh water come from?› __________________› __________________› __________________› __________________› __________________

All of these sources get their water from precipitation

How Do We Return Water

Water from crops and plants – direct ___________________

Waste water from homes/businesses – must first go through a _____________ __________› _____________– septic

tank separates out wastes from clean water

› _____________ – pipes to sewage treatment plant where water is filtered and cleaned

Activity

Discovery Education “Water Cycle Movie”

Review Questions

1. Describe in your own words what fresh water is. How much of the earth’s water is fresh water?

2. Explain how the structures of a water molecule relates to three properties of water.

3. Write a general statement describing the role of the sun’s energy in the water cycle.

4. Draw and label a diagram that traces the path of a water molecule through the water cycle.

Section 2 Surface Water

Objectives:› Describe three ways in which fresh

water exists on the surface of the earth

› Describe a water shed and its drainage systems

› Predict what life on earth might be like if freshwater didn’t accumulate on earth’s surface

Skills Warm-up

Rain Tracks› Based on your observations, what

happens to rainfall that falls on buildings where you live?

› What could happen that might change the path of the rainwater?

Different Landscapes

Some areas are forests, some are deserts

Areas are different because of the ___________ __ ____________ there

The amount of water in an area depends on the amount of ______________________

Running Water

Water from rain or melted snow can ______ into ground, ____________, or flow over as _________

Runoff forms rills and gullies to flow into streams and rivers

Running water carries water back to _______ and lets water evaporate into air

Streams and Rivers

Streams flow into rivers and rivers flow into oceans forming a _____________________

From above, a drainage system can form a tree-like pattern

______________ – a small stream that flows into a larger one

____________ drainage systems have many tributaries

Streams and Rivers

Rivers give fresh __________________

Rivers transport __________________

Land along riverbanks is good for ____________ because there is plenty of water and nutrient-rich soil

Watersheds The surrounding land area that supplies ______ to the streams of a drainage system

Can be less than 1 km to thousands of km

Watersheds that supply runoff to different drainage systems are separated by a ridge called a _____________

Rocky Mountains make up the _______________ ______________________› Streams to the _______

drain to the Atlantic Ocean› Streams to the _______

drain to the Pacific Ocean

Standing Water When running water

reaches a low area in a drainage system, it stops flowing

This low area fills with water to become› ________ – form in large,

deep depressions – sunlight doesn’t reach bottom

› ________ – form in small depressions – sunlight reaches bottom

› ________ – artificial lake built to store fresh water or prevent flooding

Frozen Water

Most of the world’s fresh water is _________

Near the poles, permanent __________ form

Snowfields turn into _____________

During short summers, some of the ice _______ supplying fresh water to many areas

The Wandering River

___________ River is the 3rd longest in the world – has >200 tributaries and 4th largest watershed

It hasn’t always been in the _______________

About every _________ years it changes course, cutting a new ____________ and abandoning its old one

The Wandering River

In Louisiana, the Mississippi has been trying to change its course __________ to the Atchafalaya River

If this happened, the port of ____________ would dry up and the cities near the Atchafalaya would flood

The army corps of engineers began a huge flood-control project

Review Questions

1. What are three ways in which fresh water exists on the earth’s surface?

2. Describe a watershed and drainage system.

3. What do you think life on earth would be like if there were ne fresh water on the surface?

Section 3 Water Beneath the Surface

Objectives:› Explain what forms groundwater

and describe groundwater zones› Describe the movements and

activities of groundwater› Predict changes in groundwater› Classify earth materials by

permeability

Skills Warm-up

Taking in Water› What happens when you water a

potted plant?› Where does the water go?› On a global scale, a huge amount of

precipitation soaks into the ground.› The amount of water underground is

more than all the world’s rivers and lakes combined.

Groundwater The water that _______

into the ground from _______ or melted _____

Groundwater fills in the _____ ________ between dirt and rock particles

_________ – the % of a material’s volume that is pore space

Materials with high porosity can hold _________

Permeability

If pore spaces are well connected, water flows easily through the rock – it is ______________

Permeable rocks› ___________› ___________› ___________

Impermeable rocks› ___________› ___________

Groundwater Zones

Water from rain or snow soaks into the ground – _________ pulls it down

Once the water reaches an impermeable layer it must __________ _____

When the water can’t spread out any further, the water level __________

Groundwater Zones

Groundwater creates two distinct zones

___________________ – lower - all pore spaces contain water

___________________ – higher – all pore spaces contain air

_____________ ___– the boundary line between the two zones

Things That Affect Water Table

_____________________› After lots of rain the

water table is higher› After a dry spell

water table is lower ______________________

______________________› Impermeable layer

close to surface – water table is higher

› Impermeable layer deeper – water table is lower

Moving Groundwater __________ – a layer of

permeable rock or sediment containing groundwater

Usually form in sandstone, sand, or gravel – above or between impermeable rock layers

Have a _______________ – exposed area where water soaks in

______________ Aquifer – largest in the U.S. – from South Dakota to Texas

Moving Groundwater

Aquifers are important sources of ______ _____

People _____ ______ into the zone of saturation and ________ water out

An _____________ gets water from an opening in a slanted, capped aquifer

Water is forced to the surface by pressure from the aquifer

Moving Groundwater

CO2 in air combines with water to form __________ _________

Acidic rainwater chemically reacts with some rocks forming _______ and __________

If water evaporates on ceiling – icicle-like ______________ form

If water evaporates on floor – pillars of minerals or ______________ form

Moving Groundwater

Groundwater can be heated by contact with: › _______________(western

U.S.)› _______________________

(eastern U.S.) ______________ – any body of

water with a temperature higher than the human body’s

___________ – a fountain of hot water ejected from the ground by superheated steam in underground chambers

Protecting Groundwater

Water is the __________ __________

As rainwater travels through materials above ground – it dissolves ___________

If the dissolved substances are harmful – the groundwater becomes ___________

Protecting Groundwater

Old landfills and dumps are a major hazard to groundwater

As rainfall moves through it dissolves chemicals in paints, cleansers, household and industrial wastes

Protecting Groundwater

_____ _________ have a lining of ______________ clay, asphalt, or plastic

Water containing dissolved chemicals can’t soak through this layer into the ground

After landfill is full, it is __________ with another impermeable layer

Groundwater is then __________ from pollution

Review Questions

1. What is groundwater? Describe two distinct groundwater zones.

2. Describe three movements and activities of groundwater.

3. What will happen to the water table in an area during a prolonged drought? What else could affect the water table the same way?

4. Order the following from least to most permeable: gravel, sand, clay, sandstone.

Lab Activity

How are a siphon and an artesian well similar?

Page 334 in textbook

Activity

Groundwater Webquest

techalive.mtu.edu/meec/module04/title.htm

Test Review

Read Chapter 14 review – page 335 and complete:

› Check Your Vocabulary› Check Your Knowledge