SI UNITS & METRIC CONVERSIONS UNIT II.2 & II.3 PPT SI UNITS & METRIC CONVERSIONS
II.2 SI UNITS SI = International system of metric units. Base unit = basic unit of measurement (all other units are multiples of base units or combinations) 1. BASE UNITS length = metre (m) mass = gram (g) time = seconds (s) amount of substance = mole (mol)
II.2 SI UNITS 2. MULTIPLES OF BASE UNITS kilo = k (103) centi = c (10-2) milli = m (10-3) **Table on page 17 – KNOW** 3. IMPORTANT EQUIVALENCES 1 mL = 1 cm3 1 m3 = 103 L 1 t = 103 kg
II.2 SI UNITS Example: Re-write the expression “6 kilograms” using PREFIX and UNIT SYMBOLS an EXPONENTIAL EQUIVALENT The prefix symbol that stands for kilo is ___ and the unit symbol that stands for grams is ___ 6 kilograms = The exponential equivalent to kilo is ____ Questions: p.19 #11-14
II.3 METRIC CONVERSIONS Metric conversions involve using unit conversions between prefix symbols and exponential equivalents. Example: Write a conversion statement between cs and s. ‘c’ stands for _____ then Questions: p.19 #15 (odds)
II.3 METRIC CONVERSIONS Example: How many millimeters are in 5 km? Unknown amount = Initial amount = Conversion factors = Combine conversion factors to make connection: Solution
II.3 METRIC CONVERSIONS Diagram (p. 20) – how prefix symbols relate to a central base unit:
II.3 METRIC CONVERSIONS Example 1: Express 7µm in Megametres. Example 2: (p.21 #16e) If 1 dL = 10-1 L and 1 kL = 103 L, how many decilitres in 0.5kL?
II.3 METRIC CONVERSIONS DERIVED QUANTITIES Derived quantity = Questions: p. 21 #16,17,18,24,28 DERIVED QUANTITIES Derived quantity = Derived unit = Example on p. 23 Question: p. 21 #29
II.3 METRIC CONVERSIONS Example 3: Convert 1cg/ mL into dg/L Unknown: Initial: Conversion factors = Solution:
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