Changes in Matter Chapter 2 Section 2
Physical Change • Physical Change: Any change that alters the appearance of matter but DOES NOT make a different substance. Examples: Changing the state of matter solid, liquid, gas Changes in shape or form dissolving, blending, crushing, chopping, breaking
Chemical Change • Chemical Change: A change in matter that produces NEW SUBSTANCES with properties different from those of the original substances. Bubbles are a sign of a chemical change…production of Carbon Dioxide Examples: Combustion burning of wood, natural gas Oxidation Rusting of iron Tarnishing Tarnish on silverware
What happens to a substance in a physical change? It changes form or appearance • Is dissolving sugar a physical change? Yes, if the water dries up, the sugar remains. • How does a chemical change differ from a physical change? Chemical change produces new substances different from those of the original substances. A B + C D + E F • When natural gas, or methane, combusts, what are the substances that combine? Is this a physical or chemical change? Methane mixes oxygen from the air. Creates CO2 & water. Chemical!
Law of Conservation of Matter • Matter is never created or destroyed…it is simply changed. • Atoms are not lost or gained, just rearranged.