What are SI Units? •  Measurement used throughout the world when performing calcula:ons related to scien:ﬁc inves:ga:ons •  Volume (cm3 =mL) Choose from: Cen:meters, ounce, grams, °C, milliliters 1.) Which unit of measurement would you use to record the mass of 10 sunﬂower seeds? 2.) Which unit of measurement would you use to record the volume of 10 sunﬂower seeds? 3.) Which unit of measurement would you use to record the temperature of a chemical reac:on? 4.) Which unit of measurement would you use to measure the length of 1 sunﬂower seed. Why is it important for scien2ﬁc measurements to be reproducible and accurate? •  If you are able to take measurements of an object and get the same result each :me, you increase your accuracy. •  All experiments should be reproducible. You should be able to do them again and get the same exact results •  What does it tell you if you don’t get the same results the second or third :me? Three important points that you should keep in mind when you record scien:ﬁc measurements 1.) You need both the measurement (for ex: 2.0, 3.4, 5.0) and the unit (g, mL, s, m) because each scien:ﬁc measurement has a very diﬀerent meaning. *Need to know what you measured 2.) Units need to be apart of an agreed upon system or measurements would not be accurate 3.) Write the measurement in proper form. This usually means using a decimal. You want your scien:ﬁc measurement to be as accurate as possible. • 
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1 inch = 2.54 cm I L = 33.8 ﬂ oz 1000 mm = 1 m 100 cm = 1 m You need to know SI unit preﬁxes à Base scale of 10 For example: kilo x1000
kilometer (1000x more than 1 meter) hecto x 100 hectometer (100 :mes more than 1 meter) deca x10 decameter (10 :mes more than 1 meter) BASE (meter, gram, liter, second) meter (1 meter) deci 1/10 decimeter (there are 10 decimeters in 1 meter) cen: 1/100 cen2meter (there are 100 decimeters in 1 meter) milli 1/1000 millimeter (there are 1000 millimeters in 1 meter) •  Density = how much maaer is occupying a certain amount of space •  = the measure of how closely packed maaer is within a given space •  If an object sinks it is DENSER than the liquid it is placed in •  If an object ﬂoats it is LESS dense than the liquid it is placed in •  Convert 80 °F to °C •  Convert 65 °F to C •  Convert 60 °C to °F •  Convert 20 °C to K •  Convert 55 °C to K •  Convert 100 K to °C