1. Metric Conversions & Rounding

2. SI Prefixes Chart Prefix Symbol Meaning kilo- k 1,000 hecto- h 100
deka- da 10
basic unit
m, g, liter 1
deci- d
.1 (one tenth)
centi c
.01 (one hundredth)
milli m
.001 (one thousandth)

3. King Henry Died of Drinking Chocolate Milk Mmmm
Conversions
To convert to a larger unit, move the decimal place to the left (divide)
To convert to a smaller unit, move the decimal place to the right (multiply)
King Henry Died of Drinking Chocolate Milk Mmmm
i e e e e i i
l c k c n l c
o t a i t l r
o i i o

4. Practice 10 grams = ? kilograms .01kg
Move the decimal three places to the left
56 meters = ? centimeters
5,600 cm
Move the decimal two places to the right
876 centimeters = ? kilometers km
Move the decimal five places to the left

5. Common SI Conversions Length Volume kilometer (km) = 1,000 m
kiloliter (kL) = 1,000 L
meter (m) = 100 cm
Liter (L) = 1,000 mL
centimeter (cm) = .01 m
centiliter (cL) = .01 L
millimeter (mm) = .001 m
milliliter (mL) = .001L
Mass
Kilogram (kg) = 1,000 g
Gram (g) = 1,000 mg
Milligram (mg) = .001 g

6. Brain Break! Lets play Gotcha!

7. Adding or Subtracting Numbers
The answer should have the SAME # of decimal places as the measurement with the least number of decimal places.
For example:
= 27.24
= (One decimal place)
= 5.35
= (One decimal place)

8. Multiplying or Dividing Numbers
answer should have the same # of digits as the measurement with the least amount of digits.
For example:
2.25 x 3 = 6.75 (3 only has one digit)
= 7
3.57 x = (3.57 has three digits)
= 12.3

9. In Labs, you will usually have to round measurements.
Rounding!
In Labs, you will usually have to round measurements.
Round to the tenths place?
10.567
= 10.6
(1 place past the decimal)
Round to the hundredths place?
=10.57
(2 places past the decimal)

10. Accuracy vs. Reproducibility/Precision
How close a measurement is to its true or actual value.
Reproducibility/Precision-
How close a group of measurements are to each other
The textbook definition of
precision is confusing. Don’t worry
about it. Reproducibility and
Precision are the same.

11. With your partner, answer the following questions…
Let’s Review
With your partner, answer the following questions…
If you are converting to a larger unit, move the decimal place to the ____________.
If you are converting to a smaller unit, move the decimal place to the ____________.
How many grams in a kilogram?
How many milligrams in a gram?
Rounding to the tenths place = ____ places past the decimal? Hundredths place = _____ places.
Using a metric ruler with millimeter markings, you measure the width of a book to be cm. How many digits can you be certain of? How many sig figs?