 # Unit I. Metric.

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Unit I. Metric

Introduction 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.

Prefixes and Units 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

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.

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 mm. Therefore 22 nm = mm.

Length Decimeter rulers (dm) 1 dm = 10 cm = 100 mm 1 cm = 10 mm

Metric ruler = 1 meter 1 m = 100 cm = 1000 mm

Millimeter (mm) and centimeter (cm) units
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) Metric units English units 1 inch

Volume 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.

The meniscus is the curved interface between the water and air
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

Equipment to measure volumes
You work mostly with pipettes: pipette pump or filling device is used to draw and dispense fluids Pipette pump 5 ml pipette Pipette with pump

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

In a laboratory you would work with:

Mass In a laboratory you would work with
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 scale

Temperature 1.8°C + 32 °C = (°F – 32) x 5/9 (°F – 32) x 0.55
The Celsius scale was named for the Swedish astronomer, Anders Celsius, who first devised it in 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

Scientific Notation 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, ⁻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, x 100, ,000 Another example is = 1.23 x 10⁻⁴. Since 10⁻⁴ = x =

Conversion Charts Weight 1 mg = ounce 1 g = ounce 1 kg = 2.21 pounds 1 oz = 28.3 g 1 lb = kg

Volume 1 ml = 0. 0338 fluid ounce 15 ml = 1 tbsp 1 liter = 4
Volume 1 ml = fluid ounce 15 ml = 1 tbsp 1 liter = 4.23 cups 1 liter = 2.11 pints 1 liter = 1.06 quarts 1 liter = gallon 1 fl oz = 29.6 ml 1 tsp = 5 ml 1 cup = 237 ml 1 pint = liter 1 quart = liter 1 gal = 3.79 liter

Length 1 mm = 0. 0394 inch 1 cm = 0. 394 inch 1 meter = 1
Length 1 mm = inch 1 cm = inch 1 meter = 1.09 yards 1 km = miles 1 inch = 2.54 cm 1 foot = m 1 yard = m 1 mile = 1.61 km End