Physical and Chemical Changes Today Define physical and

Physical and Chemical Changes Today: - Define physical and chemical changes Bag of change lab - Writing conclusions based on results. -

Chemical/Physical Change: • We will distinguish between a physical and chemical change.

Matter • Matter is anything that takes up space and has mass. • Matter is made of atoms/molecules • Matter is constantly experiencing both chemical and physical changes.

Physical Change • Physical changes occur when matter changes its appearance but not its chemical nature. • Physical property changes could include a change in state (ice melting), or size (cuting paper) • But NO new substances are formed

Physical Change

Chemical Change • Chemical changes are changes matter undergoes when it becomes • To identify a chemical change look for signs such as

Chemical Change • A chemical change occurs when fireworks are used. • Fireworks are made of metals such as magnesium and copper. These change chemically as they light up the sky.

Is it a chemical or physical change? • Sugar dissolving in tea • Chemical Change • Physical Change

Is it a chemical or physical change? • Logs burning • Chemical Change • Physical Change

Is it a chemical or physical change? • Breaking water up by separating it into hydrogen and oxygen • Chemical Change • Physical Change

Is it a chemical or physical change? • Cutting paper • Chemical Change • Physical Change

Is it a chemical or physical change? • Metal rusting • Chemical Change • Physical Change

Bag of Change Lab • In this activity you will mix three unknown substances together in a plastic bag and observe the changes that occur. Watch for changes of state (solid, liquid, gas), colour, volume, temperature, and anything else you can detect.

Hypothesis: IF. . . we combine two unknown white solids with a dark blue solution, • • THEN… I think we will observe the following changes: • __________________________

Procedure See text p. 17 #1 -6

Observations Table 1: Original Reactants Name Description Chemical A white , soft, powder, solid Chemical B Chemical C Notes -any additional info

Property Description Colour Example: turned neon green… Table 2: Description of the Properties of Products

Conclusion • Conclusions must be based on your RESULTS • A black colour, thick smoke and a strong odor were observed when bread was toasted for 30 minutes. As the colour remained when cooled, a new substance was created and a chemical reaction observed.