Name: __________________________ Date: ___________________
10.2: What is Water? (Pg. 268 – 269):
Answer the following questions:
1. Describe a particle of water. What other particles make up a particle of water?
A water particle is made up of 1 particle of oxygen and 2 particles of hydrogen.
2. You are given a sample of tap water that is clear, yellowish, and odourless. Is this a sample of pure water? Explain.
No, because pure water is clear, colourless, and odourless. Dissolved substances give water a taste, odour, or colour. In this case, some other substance must be giving the water its yellowish appearance. When water has other substances dissolved in it, it is a mixture.
3. Choose one of the states of water.
(a) Draw a labelled diagram to show the arrangement of water particles in this state.
Each water particle has one particle of oxygen (black) and two particles of hydrogen (white).
(b) Describe the arrangement of water particles in this state.
The particles of water in water vapour are far apart and move quickly in all directions. They have a great deal of energy.
10.4
10.3: The Water Cycle (Pg. 270 – 273):
Answer the following questions:
1. Look at Figure 2 (pg. 271). Where can you find each of the three states of water?
Solid water exists as ice and snow. Liquid water exists in groundwater and surface water, such as lakes.
Water vapour exists in the air.
2. Describe the water cycle. Draw your own labelled diagram. See PB Pg. 215 & TB Pg. 271
3. Briefly describe how solid and liquid water may be converted to water vapour. See PB Pg 215: Evaporation
4. Describe how water vapour changes into solid and liquid water above Earth’s surface. See PB Pg 215: Condensation
5. Does all surface runoff move directly into rivers, lakes, and oceans? Explain.
No. Some of the water seeps into the ground. It is called groundwater.
10.5: Making Water Drinkable: (Pg. 276 – 278):
Answer the following questions:
2. Is clear, colourless, and odourless drinking water always safe to drink? Explain.
No, not always. It may still contain colourless, odourless toxic chemicals or tiny living organisms, such as bacteria, that can neither be seen nor smelled but can still make people sick.
3. Describe how the membrane works in the reverse osmosis process.
In reverse osmosis, contaminated water is forced through a membrane. The membrane acts as a filter, through which only water particles can pass. The membrane traps the other substances, separating them from the water.
4. (a) Why is it important to ensure that treated water remains safe to drink when it is stored after treatment?
Bacteria and viruses can reappear in the water before it is consumed.
(b) Describe one way to make stored water safe.
Sometimes stored water is continuously exposed to UV radiation to kill any micro-organisms that might have reappeared in it.

Name: __________________________
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What Do You Remember?
1. Describe three characteristics of water at room temperature.
Date: ___________________
Pure water at room temperature is a liquid with no colour, taste, or odour.
2.
(a) Name the two kinds of particle that make up a water particle.
Hydrogen particles and oxygen particles make up water particles.
(b) How many of each kind of particle are found in a water particle?
There are two hydrogen particles and one oxygen particle in each water particle.
3. List the three states of water.
The three states of water are solid, liquid, and gas.
4.
(a) What is an aquifer?
An aquifer is a layer of rock or soil that is saturated with groundwater.
(b) Does water that collects in an aquifer remain there forever? Explain.
No, the water in an aquifer does not remain in the aquifer forever. It can be removed from the aquifer by springs, by flowing into a surface water body, or by wells dug by people.
5. Describe the role of the Sun in the water cycle.
The Sun adds thermal energy to water particles. This energy can cause snow and ice to melt or sublime, and liquid water to evaporate.

What Do You Understand?
6.
(a) Define the term “sustainability” in your own words.
Sustainability refers to the idea that people should use resources responsibly, so that the resources will still be around for use by future generations.
(b) How does your current personal water use affect sustainability?
If I can reduce my current water use, I can help preserve natural water sources so that they will be available to others in the future.
7.
(a) As water evaporates from the oceans, what happens to the total amount of water on Earth? Explain.
The total amount of water on Earth does not change when water evaporates because the water does not change into another substance; it simply changes state. The total number of water particles on Earth does not change.
(b) How does this affect living things?
The fact that evaporation does not change the amount of water on Earth means that the amount of water available for living things does not change during evaporation. However, because most living things cannot use water vapour directly, evaporation can make water temporarily less accessible to living things.

8.
(a) Describe one characteristic of water in liquid state.
Water in the liquid state can flow.
(b) Explain the characteristic of liquid water described in (a). Include a diagram that illustrates the arrangement of water particles in liquid state.
The water particles in liquid water vibrate faster than they do in a solid, and are free to move around each other in all directions. This allows the water to flow. The diagram below shows the arrangement of particles in liquid water.
10. Explain how condensation and precipitation are similar and different.
Condensation is a process. During condensation, water vapour changes into liquid water. Precipitation is liquid or solid water that falls to Earth’s surface. So, condensation and precipitation are similar because they both involve water, and they are both part of the water cycle. They are different because condensation is a process, but precipitation is a substance or material.
13. You dip a container into a small lake in northern Ontario. The water is colorless and has no odour. Would it be safe to drink? Explain.
No. Safe drinking water is odourless, colourless, and clear, but there will always be micro-organisms and/or other contaminants in lake water. These micro-organisms and/or contaminants could be harmful, so you cannot assume the water is safe to drink.
14. Not every Canadian has access to treated drinking water.
(a) Where might household tap water not go through a municipal water treatment process?
If the water is from a private well, it will not go through a municipal water treatment process.
(b) If freshwater resources are to be used sustainably, which of the following do you think will have the greatest impact: building more water treatment plants, using less water, or cleaning wastewater before returning it to the ecosystem? Explain your answer.
I choose cleaning wastewater. If we don’t clean our wastewater we may contaminate a large supply of water so that is can no longer be used. It is also wise to use less water, so that more people can share the resource.
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15. You discover a slow drip underneath the toilet tank.
(a) Research two reasons why the water is dripping.
The drip could be coming from a leak in the toilet tank. It could also be coming from condensation on the outside of the tank.
(b) How could you discover the volume of water that dripped in 24 h?
Set a bowl underneath and measure the amount of water that drips in one hour. Multiply that amount by
24 hours to get the total amount of water lost.