1. Why units matter.

2. How tall am I? 58 How meaningful is this information? How do we make it more meaningful? A number is useless unless a unit is attached. The unit provides the scale you are working in.

3. To swim for you life or not What would help you get an idea of whether or not you should stay out of this sharks way? www.konadreamhomes.com/DSC00007.JPG

4. Having a scale reference gives more info http://nynerd.com/sealion-eating-baby-shark/ www.hotfishing.com.au/images/mako-shark-1.jpg

5. Changing between units 58 inches. What other numbers does this value represent?

6. Why does this matter in chemistry? Can you count the number of atoms you are mixing? How do you measure chemicals? If you are making 4 bicycles how many wheels do you need? We do the same kind of converting with chemical equations. If I know how much salt I need then I can use conversion (dimensional analysis) to determine the amount of acid & base I need to mix together.

7. Practical applications How are cereals & chips packaged? The manufactures determine the number of packages they need to produce then back track to determine the amount of ingredients needed. Buying hardware in bulk. Money transactions. Other examples?

8. My way or the highway You will show your work when you do calculations. You will perform dimensional analysis using the strategy I outline. I will not give credit for any other strategy. I mean it. This is the one exception to the my general philosophy of wanting you to use whatever works for you to arrive at the correct answer. & I have a good reason for it. Let’s practice calculating my way.

9. Other resources Conversion factors ppt by Normal Community High School Chemistry department in Normal, IL. Conversion factors ppt