Chapter 4 – Physical Properties Glass & Soil Section 1 Pg. 89-96

Physical vs. Chemical Physical properties = describe a substance without references to any other substances Chemical properties = describe the behavior of a substance when it reacts or combines with another substance

Metric System 1791 devised by French Academy of Science Uses a simple decimal relationship Easy to convert units into subunits by multiplying or dividing Metric conversions are carried out by moving the decimal point to the right or left and inserting proper prefix Base units = length, mass, & volume Meter, gram, liter

Physical Properties Temperature – Fahrenheit & Celsius scales Science uses Celsius scale Water boils at 212 F and 100 C Water freezes as 32 F and 0 C Weight & Mass Weight = force with which gravity attracts a body Mass = amount of matter an object contains Mass never changes but weight can change depending on location

Density Mass per unit of volume Intensive property = same regardless of the size of substance Easily measured by filling a cylinder with a known volume of water (V1), adding object (m), measuring new volume (V2) m divided by V2-V1

Density continued Volume of gases and liquids vary considerably with temperature Solid object will either sink, float, or remain suspended when immersed in a liquid Sink = greater density Float = lower density Suspended = similar/same density

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