Warmup 9/21/15
How many millimeters are in a kilometer? What other
conversions between units do you know?
Objective
Tonight’s Homework
To refresh on how to convert
metric units
Finish conversion worksheet
The Metric System
Today we’re going to start discussing chemistry.
We’re going to begin with units. In chemistry, we often
need be careful with measurement because we’re often
dealing with very precise things.
So to start, let’s take notes of the different metric
prefixes and how big or small each one means.
Notes on Metric Conversion
We attach prefixes – a group of letters – in front of
each metric unit to tell us how much bigger or
smaller we want it.
prefix
letter
- mega
M
- kilo
k
- hecto
h
- deka
da
- “normal”
- deci
d
- centi
c
- milli
m
- micro
μ
size
1,000,000
1,000
100
10
1
0.1
0.01
0.001
0.000 001
Notes on Metric Conversion
To convert units, we have a simple trick.
- If we’re converting to something bigger, we move
the decimal to the left. (Divide)
- If we’re converting to something smaller, we move
the decimal to the right. (Multiply)
The letter after each prefix tells us what we’re
measuring.
m = meters
L = liters
g = grams
Example: Convert 28 mm to km.
We want to go up the table, so we need to move our
decimal left. We’re going up 6 steps, so we move our
decimal left 6.
28 mm

0.000028 km
Practice with Metric Conversion
1. 1000 cl = ____ L
2. 120 mm = ____ cm
3. 1200 cl = ____ L
4. 2 cm = ____ mm
5. 11000 L = ____ kL
6. 10 cl = ____mL
7. 12000 m = ____ km
8. 8 g = ____ cg
9. 80 ml = ____ cL
10. 3 L = ____ cL
11. 2000 L = ____ kL
12. 5 cm = ___ mm
13. 900 cm = ____ m
14. 11 cg = ____ μg
15. 900 m = __ km
16. 7000 ml = ____ L
17. 5 kg = ____ g
18. 60 mm = __ cm
19. 1 kg = ____ g
20. 4000 ml = ____ L
21. 1 cl = ____ mL
22. 1100 L = ____hL
23. 10000000 g = __ Mg
24. 20000 μl = __ L
25. 7000 L = ____ kL
26. 70 ml = ____ cL
27. 5 g = ____ cg
28. 9 cl = ____ mL
29. 1 g = ____ cg
30. 8 kg = ____ g
Exit Question
How many dekameters are in a hectometer?
a) 1
b) 10
c) 100
d) 1000
e) 0.1
f) None of the above