Day 3 (March 3) Phase change notes and worksheet Graphing assignment Density of water lab
Day 4 (March 5) Density problems Density of a paper clip lab Chemical vs. physical properties and changes
Density Mass per unit volume of a substance D = m/v
What is the density of carbon dioxide gas if 0.196 g occupies a volume of 100 mL?
A block of wood 3.0 cm on each side has a mass of 27 g. What is the density of this block?
An irregularly shaped stone was lowered into a graduated cylinder holding a volume of water equal to 2.0 mL. The height of the water rose to 7.0 mL. If the mass of the stone was 25 g, what was its density?
A 10.0 cm 3 sample of copper has a mass of 89.6 g. What is the density of copper?
A sample of iron has the dimensions of 2 cm x 3 cm x 2 cm. If the mass of this rectangular-shaped object is 94 g, what is the density of iron?
ChemicalPhysical All possible chemical changes Observed by senses; measurable properties Property Comparison
Change Comparison ChemicalPhysical Old substance destroyed; new substance formed New form of old substance; no new substances formed
Chemical Changes Substance changes composition; 1 or more new substances formed
How do you know? Production of a gas Change in color Formation of a precipitate Production of new odor Release/absorption of heat
Physical Changes Changes that occur without a change in composition Melting, freezing, etc. Dissolving
Buoyancy Tendency of a less dense substance to float in a more dense substance Ice in water; different salt water conc. in lab
Viscosity Resistance of a fluid to flow Stronger particle attraction = more viscosity Motor oils