Section 2 Units of Measurement Chapter 2 Base Units & Prefixes

Base Units Length = Meters Mass = Kilograms → We use grams in lab Time = Seconds Temperature = Kelvin Amount of Substance = Mole Section 2 Units of Measurement Chapter 2

SI Base Units Mass Mass is a measure of the quantity of matter. Standard unit is kilogram. We use gram in class and labs Mass ≠ Weight! Weight is a measure of the gravitational pull on matter. Section 2 Units of Measurement Chapter 2

SI Base Units Length The SI standard for length is the meter. The kilometer, km, is used to express longer distances The centimeter, cm, is used to express shorter distances We will also use millimeter, mm, for small distances Section 2 Units of Measurement Chapter 2

SI Conversions Section 2 Units of Measurement Chapter 2

Metric Prefixes Each prefix represents a position of the decimal Remember: King Henry Died Belly Up Drinking Chocolate Milk? * You will need to memorize these three for your test. There are other prefixes but are used less often Section 2 Units of Measurement Kilo- * Hecto-Deka-Base Unit Deci-Centi- * Milli- * 1000x100x10x10.1x0.01x0.001x 321Move decimal places 123 Chapter 2

Practice Moving Decimals to Convertunits You measure the table to be 59 cm. What is the value in meters? Millimeters? cm to m (move how many places?) 59 cm becomes how many meters…… mm to m (move how many places?) 59 cm becomes how many…… Chapter 2 Section 2 Units of Measurement m mm

Temperature Chapter 2 Section 2 Units of Measurement K =