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media type="youtube" key="6aK2CKrdjbE" height="251" width="448" __**Mr**. **Campo's Chemistry C****P** **Spring 2012**__
 * __Factor Label Method of Solving Chemistry Problems__**

The factor label method (Dimensional Analysis) is one of the best ways to solve chemistry problems. The following video downloaded from youtube will help explain why the factor label method of solving problems in chemistry is very beneficial to all students.

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 * __ Steps for Solve Problems Using the Factor Label Method __**

1.. Write down the problem. 2. Determine the units (Labels) that you want in the answer. 3. Collect all relevent information that are stated in the problem. 4. Look up conversions that are needed to solve problem. 5. Start with what is given and use a series of fractions to find out the answer to your problem. Make sure all units cancel accept for does uints that you want in your answer. 6. Solve the math part of your answer. Example: Converts 200 miles per hour to meters per second. One mile equals 1.609 km, 1,000 m equals 1 km, 1 hr contains 60 minute, and 1 minute contains 60 sec

m/sec? = (200 miles/hr) x (1.609 km/mile) x (1,000 m/1 km) x (1 hr/60 min) x (1 min/60 sec) All units will cancel accept for m/sec. Next perform the required math. 200 x 1.609 x 1,000/ (60 x 60) = 89.4

answer;: 89.4 km/sec = 200 miles/hr

Lets try another example. An apple contains 100 food calories. How many joules of energy are contained in this apple? Given 1 food calorie is equal to one kilocalore,1 kcal = 1,000 cal,and 1 cal = 4.184 joules of energy.

joules? = (100 food calories) x (1 kcal/1 food calorie) x (1,000 cal/1 kcal) x (4.184 joules/1 cal) All units cancel accept for joules. Next perform the math.

100 x 1,000 x 4.184 = 418,400

answer: 100 food calories = 418,400 joules of energy.

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