1DCHEM - PP1 (Introduction) … · October 18, 2013 1DCHEM -Introduction 1 Bubble Gum Today, the chewy, rubbery substance in gum no longer comes from natural sources. Instead,itisasyntheticmaterial

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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.

October 18, 2013 11DCHEM - Introduction

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.


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.


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.


Getting Started: Useful Concepts & Skills

CONCEPTS REVIEW

1. Which states of water are shown in the photo below?

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CONCEPTS REVIEW

2. Describe the differences between a solid and a liquid.


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CONCEPTS REVIEW

3. What are the particles in the liquid doing as the liquid evaporates?



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


M

P

P

M

M


CONCEPTS REVIEW

5. Answer the following questions.

(a) Which is more viscous (i.e. thick), water or ketchup?

(a) ketchup


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CONCEPTS REVIEW


(b) Which is denser, wood or steel?

(b) steel



CONCEPTS REVIEW


(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)



CONCEPTS REVIEW


(d) Which has a greater volume, a volleyball or a baseball?

(d) volleyball


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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.



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?



SKILLS REVIEW

8. The following diagram

shows two studentsperforming an

experiment in the lab.

Find at least five labsafety errors.


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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.



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



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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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)


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.


Documents

1DCHEM - PP1 (Introduction) … · October 18, 2013 1DCHEM -Introduction 1 Bubble Gum Today, the chewy, rubbery substance in gum no longer comes from natural sources. Instead,itisasyntheticmaterial