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WHAT IS CHEMISTRY?. The branch of science concerned with the study of matter, its composition, properties and changes. SIX MAIN BRANCHES OF CHEMISTRY. Analytical : focuses on what matter is made of (concentration) Organic: compounds containing carbon and hydrogen
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WHAT IS CHEMISTRY? • The branch of science concerned with the study of matter, its composition, properties and changes.
SIX MAIN BRANCHES OF CHEMISTRY • Analytical : focuses on what matter is made of (concentration) • Organic: compounds containing carbon and hydrogen • Inorganic: acids, bases, salts, and water • Physical: mechanism, rate and energy transfer in chemical changes • Biochemical: living things • Nuclear: changes that occur in a nucleus of an atom
WHAT IS MATTER? • Anything that has mass and volume.
HOW DO WE MEASURE MATTER? • Compare our measurements to a standard.
WHAT ARE MEASUREMENTS? • Always compared to a standard • We use the metric system in class (English system at home) • Always consist of a number and units • Ex: 35.36 g • NO NAKED NUMBERS!!!!
In the METRIC SYSTEM, a measurement has: • the number based on grouping of 10 • the unit based on seven ‘SI’ (Systeme International d’Unites) units or derived from them or metric
Physical quantity unit symbol* non-SI (accepted metric) ** Derived unit • Mass *grams g • Distance (length) meter m • Volume (liquid) *liter L • (solid) cubic meter m3 • Temperature Kelvin K • Pressure **pascal Pa
prefix meaning symbol • kilo 1000x the basic unit k • hecto 100x h • deca 10x da • Basic unit 1x • deci 0.1x d • centi 0 .01x c • milli 0.001x m • Examples: km = kilometers; cg= centigrams; mL = milliliters • kathy helps david because david can’t multiply
BE CAREFUL!!!!! • 1 gram = 0.001 kg kg is a BIGGER unit so you need less of them • 1 gram = 1000 mg mg is a smaller unit so you need more of them • 1000 mL = 1 L mL is a smaller unit so you need more of them to equal the base