The metric base unit for length is the meter (m), for mass is the gram (g), for volume is the liter (l) and for temperature is degree Kelvin (°K) but Celsius (°C) is more commonly used.

The metric system is based on the number 10 and therefore a decimal system. Prefixes precede the root or main word (gram, liter, meter). The following prefixes are commonly used in science.

2

tera (T) = 1012

giga (G) = 109

mega (M) = 106

kilo (k) = 103

hecto (h) = 102

deka (da) = 101

Unit = 10⁰= 1 deci (d) = 10-1

centi (c) = 10-2

milli (m) = 10-3

micro (µ) = 10-6

nano (n) = 10-9

pico (p) = 10-12

Meter (m) for length

Liter (l) for volume

Gram (g) for mass

3

The line below may help you with metric conversions. If you know how to convert within the metric system continue to convert the way you have learned. If you do not know how to do metric conversions then read the information below.

The base represents gram (base unit for mass), liter (base unit for volume) and meter (base unit for length). First find on the line your given, then count the number of spaces you need to move to get to your answer.

For example, look at the pink arrow above; if you have 15 kg and you want to convert it to mg then you must move the decimal point 6 spaces to the right. Your answer will be 15,000,000 mg.

4

If you have 22 nm and you want to convert to mm then looking at the ruler below, you must move 6 spaces to the left. In other words, you move your decimal point 6 spaces to the left. Your answer is then 0.000022 mm. Therefore 22 nm = 0.000022 mm.

5

Decimeter rulers (dm)

1 dm = 10 cm = 100 mm

1 cm = 10 mm

6

Metric ruler = 1 meter

7

cm 0 10 20 30 40 50 60 70 80 90 100

mm 0 100 200 300 400 500 600 700 800 900 1000

1 m = 100 cm = 1000 mm

Millimeter (mm) and centimeter (cm) units. Take a look at your ruler and find the units below. Notice that one inch is approximately 2.5 cm.

1 millimeter (1 mm) 1 centimeter ( 1cm)

1 inch

Metric units

English units

8

When a figure has three dimensions we can find its volume. Volume can be expressed in terms of liters or cubic centimeters (cm3 or cc). Larger volumes can be expressed as m3 and dm3. The base unit of measurement for volume is the liter.

Note: 1 liter = 1000 ml = 1000 cm³

1 dm3 = 1000 cm3 The liquid in one liter will fit in a dm3 so; 1 liter =

1 dm3 This means that 1 cc = 1 ml.

9

The meniscus is the curved interface between the water and air. This is due to the surface tension and adhesive forces of water as it interacts with its container

meniscus

In pure water 1 ml = 1 cc = 1 g

10

You work mostly with pipettes: pipette pump or filling device is used to draw

and dispense fluids

Pipette pump

5 ml pipette

Pipette with pump11

Pipettes of different sizes

The 1 ml, 5 ml and 10ml pipettes can dispense as little as 1/10 ml.

1 ml pipette

5 ml pipette

10 ml pipette

12

In a laboratory you would work with:graduated cylindersErlenmeyer flasksBeakers

13

Mass is a measurement of the amount of matter in an object. It is determined by the molecular structure of the object. Weight is a measure of the gravitational pull on an object. It is not the same as mass.

Remember, pure water only : 1 cc = 1 ml = 1 g

In a laboratory you would work with Triple beam balance Electronic scale

Triple beam balance Electronic scale14

The Celsius scale was named for the Swedish astronomer, Anders Celsius, who first devised it in 1742. The Celsius thermometer was called the centigrade thermometer because it had 100 (centi) degrees between the freezing point of water and the boiling point of water. The Celsius scale is used to measure temperature in the metric system. Conversions can be done between degrees Celsius and degrees Fahrenheit.

°F = 9/5°C + 32 1.8°C + 32

°C = (°F – 32) x 5/9 (°F – 32) x 0.55

15

Scientific notation uses powers of 10 so very large or small numbers can be expressed concisely. The number we use as the base for this system is 10. The exponent is the power of the number and is applied to the base. For example, if the exponents were 0, 3, and -3, when applied to the base of 10 you have:

10⁰= 1 10³ = 1,000 10⁻³ = 1/1,000 or 0.001

Every time you increase the exponent by 1, you are multiplying by 10. If you decrease the power by 1, you are dividing by 10. For example 123,000 is 1.23 x 10⁵. Since 105 = 100,000 1.23 x 100,000 123,000

Another example is 0.000123 = 1.23 x 10⁻⁴.

Since 10⁻⁴ = 0.0001 1.23 x 0.0001 = 0.00012316

Weight1 mg = 0.0000353 ounce1 g = 0.0353 ounce1 kg = 2.21 pounds1 oz = 28.3 g1 lb = 0.454 kg

17

Volume1 ml = 0.0338 fluid ounce15 ml = 1 tbsp1 liter = 4.23 cups1 liter = 2.11 pints1 liter = 1.06 quarts1 liter = 0.264 gallon1 fl oz = 29.6 ml1 tsp = 5 ml1 cup = 237 ml1 pint = 0.474 liter1 quart = 0.941 liter1 gal = 3.79 liter

18

Length1 mm = 0.0394 inch1 cm = 0.394 inch1 meter = 1.09 yards1 km = 0.622 miles1 inch = 2.54 cm1 foot = 0.305 m1 yard = 0.914 m1 mile = 1.61 km

End

19