1dchem - pp1 (introduction) … · october 18, 2013 1dchem -introduction 1 bubble gum today, the...
TRANSCRIPT
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SNC1DCHEMISTRY
ATOMS, ELEMENTS, & COMPOUNDS
L Introduction
(P.130-133)
Bubble Gum
What makes a chewing gum so good? Isit the taste, the texture, or the size of thebubble you can blow? People have beenchewing gum for thousands of years.Stone Age people chewed birch bark tar,which forms when the bark is heated.Native peoples of North America chewedthe sap of spruce trees.
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Bubble Gum
Today, the chewy, rubbery substance ingum no longer comes from naturalsources. Instead, it is a synthetic materialmade form the chemicals found in oil.The scientists who develop thesesynthetic “gum bases” design them forthe type of gum that they want to make.For example, the gum bases used forregular chewing gum have differentproperties than those used in bubble gum,which needs to be more elastic.
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Bubble Gum
But there are more substances in gumthan just the rubbery stuff. Look at theingredients on the package. Carnaubawax, for example, is an ingredient inmany types of chewing gum. It comesfrom tree leaves, and it gives the gum adry, shiny coating. Carnauba wax is alsofound in car wax, shoe polish, and dentalfloss! Shellac, which comes from a typeof insect, is used to give wood furniture apolished finish. It is also used to givemany types of chewing gum a shinyappearance.
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Bubble Gum
Substances are added for flavouring. Forexample, sorbic acid and malic acid givegum a sour apple flavour. Chocolate-flavoured chewing gum cannot be madebecause the cocoa butter in chocolatemakes the gum too soft to be chewed.
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Overall Expectations
By the end of this unit, students will:
1. assess social, environmental, and economic impacts of the use of
common elements and compounds, with reference to their physical andchemical properties;
2. investigate, through inquiry, the physical and chemical properties of
common elements and compounds;
3. demonstrate an understanding of the properties of common elements
and compounds, and of the organization of elements in the periodictable.
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Big Ideas
Concepts that students should retain long after this unit are:
< Elements and compounds have specific physical and chemical
properties that determine their practical uses.
< The use of elements and compounds has both positive and negativeeffects on society and the environment.
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
1. Which states of water are shown in the photo below?
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
2. Describe the differences between a solid and a liquid.
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
3. What are the particles in the liquid doing as the liquid evaporates?
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
4. Classify each of the following as either a pure
substance or a mixture:
(a) hot chocolate
(b) distilled water
(c) oxygen
(d) sugar dissolved in water
(e) pizza
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
5. Answer the following questions.
(a) Which is more viscous (i.e. thick), water or ketchup?
(a) ketchup
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
5. Answer the following questions.
(b) Which is denser, wood or steel?
(b) steel
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
5. Answer the following questions.
(c) Which has more mass, one kilogram of lead or one kilogram of
wool?
(c) both have a mass of one kilogram (densities are different)
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
5. Answer the following questions.
(d) Which has a greater volume, a volleyball or a baseball?
(d) volleyball
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
6. Liquid flowing into the stream in the photo comes from an abandoned
farm. What possible environmental effects could this have? Givereasons for your answer.
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Getting Started: Useful Concepts & Skills
CONCEPTS REVIEW
7. Batteries contain heavy metals (such as nickel, cadmium, and lead) and
are responsible for over 50% of the heavy metals found in landfills.Why should batteries be recycled instead of being discarded?
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Getting Started: Useful Concepts & Skills
SKILLS REVIEW
8. The following diagram
shows two studentsperforming an
experiment in the lab.
Find at least five labsafety errors.
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Getting Started: Useful Concepts & Skills
SKILLS REVIEW
9. Give reasons for the following safety procedures.
(a) Wash your hands after handling chemicals.
(b) Close the containers of unused chemicals promptly after use.
(c) Read the safety labels of all chemicals you use.
(d) Check with your teacher before disposing of chemicals in the sink.
(e) Never pour unused chemicals back into the stock bottle.
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Getting Started: Useful Concepts & Skills
SKILLS REVIEW
10. A block of wood has a density of 0.95 g/cm3. Will it float or sink when
placed in a liquid with a density of:
(a) 1.00 g/mL?
(a) the wood will float since its density is < 1.00 g/mL
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Getting Started: Useful Concepts & Skills
SKILLS REVIEW
10. A block of wood has a density of 0.95 g/cm3. Will it float or sink when
placed in a liquid with a density of:
(b) 0.88 g/mL? Explain your answer.
(b) the wood will sink since its density is > 0.88 g/mL
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Getting Started: Useful Concepts & Skills
SKILLS REVIEW
11. You are heating a 500 mL solution in a glass beaker and recording its
temperature every 2 min during an experiment. What is your:
(a) independent variable?
(b) dependent variable?
(c) control variable(s)?
(a) time (i.e. variable being manipulated or changed)
(b) temperature (i.e. variable being observed or measured)
(c) volume & container (i.e. variable(s) being controlled)
October 18, 2013 1DCHEM - Introduction 21
Activity: Plastic World (B1/P.132)
ISSUE
We use plastics for a multitude of uses. We also use plastic bags to carry
groceries, package food, and contain garbage. So why should plastics andplastic bags be of such a concern to us?
INSTRUCTIONS
A. Read the article “B1: Plastic World”.
B. Answer Q.1-3/P.133
C. As a class/group, discuss/compare your answers.
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