Conversion Factors

Flashback What is the mass of a book that has a volume of 2800 cm3 and a density of 1.05g/cm3?

A conversion factor is a ratio derived from the equality between two units that can be used to convert from one unit to the other. For example, is you wanted to know how many days are in a week, you write an equality that relates days and weeks. 7 days = 1 week

From this equality, you can write two conversion factors: 7 days 1 week 1 week 7 days

If you wanted to change 14 days to weeks, you would do the following: 14 days x 1 week = 2 weeks 7 days Notice that we used the conversion factor that had the unit we were finding(weeks) in the numerator( the top of the ratio).

Study Check As long as you know the relationship between the unit you have and the unit you want, you can write an equality and then the conversion factors. 1kg = ____________g Conversion factors:

Study Check Complete the following conversions: 0.014 mg= ________g 1.57 km = ________ m 1.2 L = __________mL 3.58cm3 = ______m3 16.45m = ______km 5.172g = _______kg