Explanation:
Here, I am talking about converting units for a specific quantity. For example, converting a volume from m3 to L, or converting mass from kg to lb-m (pound-mass). This is done by multiplying the quantity you want to change by conversion factors, so that the units cancel giving the desired units. Now, to illustrate how to perform a unit conversion, let's work out the following problem. Knowing that 2000 lb = 1 ton, and 1 kilogram = 2.205 lb., determine the mass of a 3 ton garbage truck in kilograms? We want to start with the 3 tons on the left hand side, and write the unit conversions as fractions so that the units cancel. Example 2.a.1: A 5 gallon bucket of tar weighs 30 lb. (pound-mass). What is the mass of the bucket in SI units (kg)?
Example 2.a.2: For the same bucket as above, what is the volume in SI units (m3)
Example 2.a.3: An 8 oz. cup of water is filled to the brim. How many liters is this?
Example 2.a.4: Solve 2.a.3 again, but this time determine how many grams of water are in the cup. Remember that the density of water is 1 g/mL.
Example 2.a.5: Find the number of gram-moles in the 8 oz. cup of water.
Example 2.a.6: Find the number of pound-moles in the 8 oz. cup of water.
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