Unit 1: Nature of Chemistry

Content Outline: Math – The Language of Science (1.4) – Part 1

  1. ______ (Basically, changing one unit/dimension into another unit/dimension.)
  1. This is the mathematical expression of relationship between two ______sets of units, that are related; but in the form of a ratio/fraction. For example, you know than $1 is equal to 4 quarters (0.25) and that a quarter (0.25) is equal to 5 nickels (0.05). See the relationships below:

$1.00 = 4 Quarters; 1 quarter = 5 nickels ; therefore $1 = 20 nickels (4 x 5)

Notice that each part of the fraction ______and ______add up to theto the same

Quantity. So each ratio equals 1.

  1. ______ – this term refers to the top number in the fraction.
  2. ______– this term refers to the bottom number in the fraction.
  3. ______start by listing your units (They must have a ______relationship or it will not work.) and then put in your numbers.
  1. ______
  1. This is a mathematical technique that allows you to use units to solve problems involving measurements (remember measurements need units). The basic premise is this:

This ______allows us to ______ the ______unit of measurement and ______ with the ______unit of measurement. For example:

You know that your desk is 3 feet wide. How many inches is that?

Notice we used the conversion factor of 1 foot being equal to 12 inches; BUT notice the unit placement so that we could convert/replace the given unit with the wanted unit.The units must work in converting or you cannot solve the problem.

  1. ______ (These are ______in measurements.)
  1. Consists of ______and one final digit ______
  2. All digits 1 – 9 are considered ______. For example:
  1. The significance of zeros______ within the number.
  2. The four rules of zeros apply:
  1. Zeros appearing ______non-zero digits are significant. For example:
  1. Zeros appearing ______of a number and to the ______ of the decimal point are significant. For example:
  1. Zeros ______but to the ______may or may not be significant. It depends on ______For example:

The zeros in the first number ______. The presence of the decimal point indicates that they ______ as in the second example.

  1. Zeros appearing ______ of all non-zero digits are not significant, as they too are considered “place holders”. For example:
  1. ______or ______involving significant figures:
  1. When adding OR subtracting decimals, the answer must have the ______to the ______ of the decimal point as there are in the measurement ______. For example:
  1. ______or ______ involving significant figures:
  1. When multiplying OR dividing, the answer must have ______ For example:
  1. The rules for D and E do not apply when using ______ as those conversions are considered as ______For example: