Matter and Energy Chapter 2

Bellwork 10/13/09 Calculate the following Density – refer to pg. 43 if you don’t remember how to calculate density 1.A piece of clay has a mass of 250 g and a volume of 10 cm^3. What is the density of the clay? (please show your work) 2.A block of gold has a mass of 15g and a volume of 3 cm^3. What is the density of the gold? (please show your work.

Vocab 2.1 Use your book to look up the following vocab words and make a 4-square chart for each. physical property p.41 density p. 43 physical change p. 44 chemical property p.46 chemical change p.46

Vocab 2.1 physical property – characteristics of a substance that can be observed without changing the identity of the substance density – measure of the amount of matter present in a given volume of a substance (d = m / v) physical change – a change in any physical property of a substance

Vocab 2.1 (cont) chemical property – a characteristic of a substance that describes how it can form a new substance. chemical change – a change of one substance into another substance

Bell Work 10/14/09 1.List 3 examples of physical properties. 2.Give an example of a physical change. 3.List 3 examples of chemical properties. 4.Give an example of a chemical change.

Bell work 10/20/09 1.What is a physical change? (list a few characteristics) 2.What is a chemical change? (list a few characteristics)

Bell Work 10/21/09 Describe your favorite station yesterday. Was it a chemical or physical change?

Bell Work 10/22/09 Decide if the statements are true. If not, correct them. Density is a chemical property. Cutting a carrot in half is a physical change. Silver tarnishing is an example of a physical change.

2.2 Vocab Melting – the process by which a solid becomes a liquid Melting point – the lowest temperature at which a substance begins to melt Freezing – the process by which a liquid becomes a solid Freezing point – the temperature at which a specific liquid becomes a solid

2.2 Vocab Cont. evaporation – the process by which a liquid becomes a gas sublimation – when a solid changes directly to a gas (dry ice) boiling – a liquid becomes a gas and bubbling occurs Boiling point – the temperature a liquid must reach in order to boil Condensation – the process where gas changes its state to become a liquid

Bell Work 10/23/09 1.What is melting? 2.What is freezing? 3.Compare and contrast melting point and freezing point. (at least 2 sentences)