FACTOR LABEL METHOD FACTOR LABEL METHOD In math

FACTOR LABEL METHOD

FACTOR LABEL METHOD In math you use numbers, in chemistry we use quantities. l A quantity is described by a number and a unit. l 100 is a number : 100 Kg is a quantity l

Sometimes You Have to Convert Between Different Units • How many seconds are in a day? l • How many inches are in a centimeter? l • If you are going 50 miles per hour, l how many meters per second are you l traveling? l • To answer these questions you need l to change (convert) from one unit to l another. l

what is dimensional analysis? The converting from one unit system to another. l If this is all that it is, why make such a fuss about it? Very simple. Wrong units lead to wrong answers. Scientists have l thus evolved an entire system of unit conversion. l

How does it work? • It will involve some easy math (Multiplication & Division) l • to perform any conversion, you need a conversion factor. l • Conversion factors are made from any two terms that describe the same or equivalent “amounts” of what we are interested in. l For example, we know that: l 1 inch = 2. 54 centimeters l 1 dozen = 12 l

l 3. 5 miles = ____m

l 3 m= ______in

l 350 g = _____ lbs

6 gal= _____ fl oz l (1 gal = 4 qts) (1 qt = __fl oz) l

l 7 days =_______seconds

. How many basketballs can be carried by 8 buses? l· 1 bus = 12 cars · 3 cars = 1 truck · 1000 basketballs = 1 truck

30 oranges = ______pineapples l 1 pear = 2 melons l 2 pineapples= 3 melons l 5 pears= 4 oranges

PRACTICE 2. How many grams in 150 pounds given the equalities 1 pound = 0. 454 kg and 1 kg = 1000 grams? l

l 1. How many yards = 50 meters? (HINT: yards…feet…meters) l 2. How many seconds are in 15 hours? l 3. How many ounces are in 3. 27 tons if (1 ton = 2000 pounds) & (16 oz = 1 lb) l 4. Convert 399, 338 inches to miles. (5280 feet = 1 mi)

l 5. 12. 82 kiloliters convert to m. L? l 6. How many seconds are in 17 days? l 7. How many ML are in 3. 5 gallons? (4 quarts = 1 gal) l 8. 2 miles = ____km

l 9. Convert 9 gal to ML l 10. Convert 12 meters to feet