Spring Break Chemistry -A WebQuest

Prepared by Renee Hill and Teresa McDonald

At long last it's Spring Break! You and your friends plan to spend the week basking in the sun at the beach. All thoughts of chemistry are banished from your mind. Or are they? How does that sunscreen work? How do your new shades darken automatically? Why do the grains of sand in your sand castle stick together?

Your teacher is always saying, "Chemistry is everywhere!” Could she be right? Could chemistry actually intrude on your Spring Break? Complete the WebQuest and find out!

Tan Without the Sun!

What makes self-tanning solutions work?

http://pubs.acs.org/cen/whatstuff/stuff.html

What is the active ingredient in self-tanning products and what source do companies use to obtain this chemical?

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Often, discoveries in science are made by “accident”. Explain how the effects of DHA on the skin were discovered.

Name and describe the chemical reaction that causes the skin to turn brown.

Do artificial tans protect you from the burning rays of the sun? Why or why not?

Don’t go for the burn! Use Sunscreen!

If the “tan in a can” does not appeal to you, hit the beach to get some color. Don’t forget your sunscreen. Understanding how sunscreen works can help you to use it more effectively. Go to the site below to find out more!

http://www.sfsu.edu/~shs/skinclinic/sunscreen.htm

The action of sunscreen may be either physical or chemical. Explain the difference between the two regarding their contents and how they work.

Is a tanning bed a safer alternative than the beach? Why or why not?

In the Shade

As you lie on the beach, a cloud suddenly masks the sun. Luckily, the sunglasses you are wearing are photochromic and they lighten automatically. Could chemistry have anything to do with this? Of course! Go to the site below and scroll down to the section on Photochromic Sunglasses.

http://www.howstuffworks.com/sunglass4.htm

What molecules are the photochromic lenses coated with and how do they cause darkening?

Under what circumstances might the photochromic lens not react to light?

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Castle Chemistry

What could be more fun than building a castle in the sand? The only thing that could make it better is understanding the chemistry behind the structure. Click on the link below to find out why sand “sticks”.

http://netaxs.com/~sparky/answers.html

Two factors determine how well the sand in a castle sticks together. What are those factors?

What problem is created if the sand is too wet?

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Why do some castles continue to stand even after they dry?

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Keeping Your Suit On!

Lycra is the miracle fabric of the century. It helps keep the stretch in your swimsuit and adds durability to delicate fabrics. Find out more at

http://pubs.acs.org/cen/whatstuff/stuff.html

Lycra is actually just a trade name for a fiber that has been around for many years called ____________________________.

In what ways is Lycra superior to rubber thread?

After reading about Lycra/spandex, what one property of the polymer do you think is most important when the fiber is used in swimsuits?

The article mentions some future potential uses for Lycra/Spandex. Suggest at least two other possible uses of your own.

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Pause for Refreshment!

You’ve been baking in the hot sun for hours. It's time for a soda and a snack. Rumors about junk food abound. Does soda really rot your teeth? Can chocolate make you happy? Do Pop Rocks really explode in your mouth? Check out the links below and investigate these rumors.

Pop Rocks Candy

Pop Rocks candy feels like it explodes in your mouth when you eat it. In fact it sort of does explode. To find out what makes the “POP!” in Pop Rocks, go to

http://www.howstuffworks.com/question114.htm

When making hard candy, the ingredients are heated to a boil then to 300 ^o F. What is the purpose in heating the candy to this extreme?

What might the candy be like if it were not heated long enough or to a high enough temperature?

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Explain why Pop Rocks pop!

Sweet Chemistry: Chocolate

Have you ever craved a chocolate bar when you were down? Can chocolate really make the blues go away? Find out more at:

http://www.americanchemistry.com/chemmag.nsf/WebMagazineArticle?ReadForm&mfik-4tjqax

How is chocolate liquor made and what two products are derived from the liquor?

You have probably heard that chocolate can make your dog very ill. What chemical in chocolate is harmful to dogs and why?

A chemical in chocolate can elevate your mood. What is the chemical and how does it affect your brain?

http://www.americanchemistry.com/chemmag.nsf/WebMagazineArticle?ReadForm&mfik-4tkmh4

A Chemical Brew

It’s hot! You want something cool and refreshing. How about an ice cream float? Did you know that a float is practically a chemical laboratory? Check out the ice cream at the link:

http://www.harcourtcollege.com/chem/general/joesten/student/add/chapters/icecream.html

The ice cream in your float is actually a colloid. What is a colloid and is it homogeneous or heterogeneous?

A colligative property is when the addition of a solute to a solvent alters the boiling point or freezing point of a solvent. This property is in effect both in the manufacture of ice cream and in the ice cream itself. Explain.

When you were young, perhaps you tried to dissolve a chicken bone, tooth, or egg shell in Coke. What gives Coke this ability? Read on.

http://antoine.frostburg.edu/chem/senese/101/consumer/faq/why-phosphoric-acid-in-soda-pop.shtml

What acid is added to soda pop and why is it added?

What acids are found in fruit drinks?

When you can’t hit the beach…

Maybe it is raining. Maybe you have to baby-sit your younger siblings. If you need something to do why not revisit the past and play with some Silly Putty! While you’re at it why not learn a little chemistry at the same time!

Go to the link below then click on the Silly Putty timeline to find out how and why Silly Putty was created.

http://www.sillyputty.com/history_101/history101.htm

How was Silly Putty created and for what purpose?

In 1995, color changing Silly Putty was introduced. Go to the following link to see how color changing Silly Putty works.

http://www.sillyputty.com/silly_science/science_faqs.htm

How does color change Silly Putty work?

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Is Silly Putty a liquid or solid? Explain.

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Have a better Spring Break with the help of CHEMISTRY!