1. Science Review
4 versus 5
Waste and Our World
v.
Classroom Chemistry

2. Grade 4:
Unit Understandings
1. Identify plant and animal wastes, and describe how they are recycled
in nature. For example, plant leaves serve as a source of food for soil
insects, worms and other creatures. The wastes of these animals may
then be further broken down by molds, fungi and bacteria.
2. Identify and classify wastes that result from human activity.
3. Describe alternative methods of disposal, and identify possible
advantages and disadvantages of each.
4. Distinguish between wastes that are readily biodegradable and those
that are not.

3. 5. Compare different kinds of packaging, and infer the relative
advantages and disadvantages of that packaging. In evaluating
different forms of packaging, students should demonstrate the ability
to consider a consumer perspective as well as an environmental
perspective.
6. Identify methods of waste disposal currently used within the local
community.
7. Identify kinds of wastes that may be toxic to people and to the
environment.
8. Identify alternative materials and processes that may decrease the
amount of waste produced; e.g., reducing wastage of food, using
both sides of a sheet of paper.

4. 9. Identify ways in which materials can be reused or
recycled, including examples of things that the student
has done.
10. Develop a flow chart for a consumer product that
indicates the source materials, final product, its use and
method of disposal.
11. Identify actions that individuals and groups can take
to minimize the production of wastes, to recycle or
reuse wastes and to ensure the safe handling and
disposal of wastes.

5. Grade 5: Unit Understandings
1. Recognize and identify examples of the following kinds of mixtures:
· two or more solids; e.g., sand and sugar
· a solid and a liquid; e.g., sugar and water
· two or more liquids; e.g., milk and tea.
2. Apply and evaluate a variety of techniques for separating different
materials.
3. Distinguish substances that will dissolve in a liquid from those that
will not, and demonstrate a way of recovering a material from
solution.
4. Demonstrate a procedure for making a crystal.

6. Grade 5: Unit Understandings
5. Recognize that the surface of water has distinctive properties, and
describe the interaction of water with other liquids and solids.
6. Produce carbon dioxide gas through the interaction of solids and
liquids, and demonstrate that it is different from air.
7. Distinguish reversible from irreversible changes of materials, and
give examples of each.
8. Recognize and describe evidence of a chemical reaction. Explain
how the products of a reaction differ from the original substances.
9. Use an indicator to identify a solution as being acidic or basic.

7. • You have 30 seconds from when I say go to
make a chart on the whiteboard that lists two
human wastes and two plant wastes.
HUMAN WASTES PLANT WASTES
* *
* *

8. • You have 30 seconds from when I say go to
make a chart on the whiteboard that lists two
human wastes and two plant wastes.
HUMAN WASTES PLANT WASTES
* *
* *
• What is the main difference between these
two wastes?

9. • Here you are given 3 mixtures. Name what
type of separation method would work best.
Explain why you chose that method.
Mixture Sand and Iron Salt and Sand Flour, Sand
and Pebbles
Method

10. • Moulds, fungi, bacteria and worms all help
natural wastes break down into soil. What do
we call these?

11. • Moulds, fungi, bacteria and worms all help
natural wastes break down into soil. What do
we call these?
• Answer: Decomposers

12. • Please list 3 substances that will dissolve in
water and 3 substances that will not dissolve
in water.
Substances that dissolve Substances that do not
dissolve
1. 1.
2. 2.
3. 3.

13. Garbage Disposal
• List a disadvantage (something that is bad)
about getting rid of garbage by the following
methods:
• Burning it
• Dumping it

14. Garbage Disposal
• List a disadvantage (something that is bad) about
getting rid of garbage by the following methods:
• Burning it
• Dumping it
• Answer: Burning garbage releases toxic chemicals
into the air
• Dumping garbage when the ground is not lined
will allow dangerous liquids to absorb into the
ground and water supplies

15. • Please give a descriptive explanation of how
you can make a salt crystal.

16. Please give a descriptive explanation of how you
can make a salt crystal.
• Boil water
• Add 3 cups of the boiling water to a container
• Add salt until the substance is saturated
• Suspend a thread over the mouth of the jar so
that the thread touches the water
• Wait 1-3 weeks to observe growth
– Do you know why boiling water is used rather than
room temperature water?

17. • List 3 things you can put into a composter.
(only one can be fruit/vegetable related)

18. • List 3 things you can put into a composter.
(only one can be fruit/vegetable related)
• Fruit and vegetable remains
• Coffee grounds
• Egg shells

19. • Annie is growing crystals in class. She wants to
know if using sugar, instead of salt, will result
in a faster growing crystal. What is her
testable question?

20. • Annie is growing crystals in class. She wants to
know if using sugar, instead of salt, will result in a
faster growing crystal. What is her testable
question?
• How does using sugar, rather then salt, affect the
rate of growth of a crystal?
• Remember the formula “How does ‘manipulated
variable’ effect ‘responding variable’.

21. What does the word ‘biodegradable’ mean?
Give one example of something that is not
biodegradable.

22. What does the word ‘biodegradable’ mean?
Give one example of something that is not
biodegradable.
Answer: Plastic
*Technically all things are biodegradable, but
some things can take hundreds of years to break
down, such as plastic or aluminum.

23. • When we fill a jar with water, it forms a dome
like skin. What term do we use to describe
what causes this? Explain what this term
means.

24. • When we fill a jar with water, it forms a
convex (dome-like) skin. What term do we use
to describe what causes this? Explain what
this term means.
• This is caused by surface tension. Surface
tension is caused the water molecules are
attracted to each other, which causes water
beading and the convex skin.

25. • For lunch your parents take you to Subway.
You order a sub. The vendor makes your
sandwich, wraps it in paper, puts a napkin
around it, and then places it in a plastic bag.
• What is wrong with this scenario?

26. • For lunch your parents take you to Subway. You order a
sub. The vendor makes your sandwich, wraps it in
paper, puts a napkin around it, and then places it in a
plastic bag.
• What is wrong with this scenario?
• What can you do to reduce waste in this situation?
• What can you ask the business to do in order to reduce
was in this situation?

27. • Cold water is _____________ dense than hot
water
• Ice cubes are ________________ dense than
cold water

28. • Cold water is more dense than hot water
• Ice cubes are less dense than cold water
• Water is its most dense around 4 degrees,
then it becomes less dense.

29. • List 3 different waste disposal programs in
Lethbridge

30. • List 3 different waste disposal programs in
Lethbridge.
• Recycling Depot
• Grasscycling
• Backyard composting
• Christmas Tree Collection
• Leaf Fall Collection
• Waste and Recycling center (includes hazardous
wastes)

31. • What is one way we can create carbon dioxide
by mixing a solid and a liquid?
• How can we test to make sure that carbon
dioxide is created?

32. • What is one way we can create carbon dioxide by
mixing a solid and a liquid?
• How can we test to make sure that carbon
dioxide is created?
• Answer: Baking Soda and Vinegar. We can test it
by placing a candle in the bottom to observe
whether the flame is extinguish. If this happens,
we know that carbon dioxide is present.

33. What do the symbols stand for? Give an
example of each one.

34. What do the symbols stand for? Give an
example of each one.

35. • List 3 things that make carbon dioxide
different from oxygen

36. • List 3 things that make carbon dioxide
different from oxygen
• Tasteless
• Odourless
• Heavier than air
• Does not allow fire to burn

37. • Give an example of how you can reuse the
following things:
• Glass Jar
• Empty Milk Carton

38. • When observing changes, what four signs can
we look for in order to identify whether or not
a chemical change has occurred?

39. • When observing changes, what four signs can
we look for in order to identify whether or not
a chemical change has occurred?
• Colour Change
• Bubbles
• Precipitate
• Heat is released

40. Remember this…

41. • You have one minute to discuss and decide on
at least two materials needed for a bike and
where those materials come from.

42. • If a change is reversible, we call it a
________________ change. An example of
this is _________________________.
• If a change is irreversible, we call it a
________________________ change. An
example of this is
___________________________.

43. • If a change is reversible, we call it a physical
change. An example of this is dissolving salt in
water.
• If a change is irreversible, we call it a chemical
change. An example of this is frying an egg.

44. • List 3 ways that you can reduce waste. This
does not include recycling things.

45. • List 3 ways that you can reduce waste. This
does not include recycling things.
• Using a re-useable lunch kit
• Saving jars and plastic containers to re-use
• Picking up litter
• Using both sides of the paper

46. • If a solution is acidic, it will turn red litmus
paper _____________ and blue litmus paper
______________.
• If a solution is basic, it will turn red litmus
paper _______________ and blue litmus
paper _________________.

47. • If a solution is acidic, it will turn red litmus
paper red (will not change) and blue litmus
paper red.
• If a solution is basic, it will turn red litmus
paper blue and blue litmus paper blue (will
not change).

48. • Do all the members of your group vow to be
more green and look after the Earth for future
generations?
• Explain why agreeing to make this decision is
important.

49. • When we look at a pH scale, it shows us how
acidic or basic a solution is.
• Drain cleaner is listed as a 14. This means it is
very ___________________
• Distilled water is listed as a 7. This means it is
______________________.

50. • When we look at a pH scale, it shows us how
acidic or basic a solution is.
• Drain cleaner is listed as a 14. This means it is
very basic
• Distilled water is listed as a 7. This means it is
neutral.

51. • List 3 main point about how a Water
Treatment Plant Works

52. • List 3 main point about how a Water Treatment
Plant Works
Answer:
• Waste (not sludge) falls to the bottom of a tank
and is taken to the dump
• Bacteria eats the wastes
• Clean water is released into the river
• Sludge is ‘digested’ and spread over crops

53. Please explain the three types of matter using
the words volume, shape, indefinite, definite

54. Please explain the three types of matter using
the words volume, shape, indefinite, definite
• Solids have definite shape and definite
volume
• Liquids have definite volume and indefinite
shape
• Gases have indefinite volume and indefinite
shape

55. Give 2 reasons way saving and protecting clean
water is so important (think back to the videos
we watched)

56. Give an example of something that is extremely
acidic. What number would it have on the pH
scale?

57. Give an example of something that is extremely
acidic. What number would it have on the pH
scale?
Battery Acid (1)
Stomach Acid (2)

58. • List 3 ways that you can save water

59. • List 3 ways that you can save water
• Turning off the water while brushing your
teeth
• Taking short showers instead of baths or long
showers
• Not polluting rivers or storm water

60. What problem might we have if we were testing
acidic and basic solutions, but only had blue
litmus paper?

61. What might we have a problem doing if we were
testing acids and bases, but only had blue litmus
paper?
If it turns red, you know it is an acid. But if the
paper does not change colour, you cannot know
if it is a base or neutral.