Warmup 9/21/15

How many millimeters are in a kilometer? What other conversions between units do you know?

Objective Tonight’s HomeworkTo refresh on how to convert metric units

Finish conversion worksheet

The Metric SystemToday 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 ConversionWe 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 size- mega M 1,000,000- - - kilo k 1,000- hecto h 100- deka da 10- “normal” - 1- deci d 0.1- centi c 0.01- milli m 0.001- - - micro μ 0.000 001

Notes on Metric ConversionTo 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 Conversion1.  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) 1b) 10c) 100d) 1000e) 0.1f) None of the above