PROPERTIES 500 mL 25 o C 10 cm long What could it be??? Anything! EXTENSIVE PROPERTIES – depends on amount 1 g/mL Clear, colorless Odorless MP 0 o C BP 100 o C What could it be? We have an idea! INTENSIVE PROPERTIES – do not depend on amount

Calculations Using Temperature Generally require temps in kelvinsGenerally require temps in kelvins T (K) = t (˚C) T (K) = t (˚C) Body temp = 37 ˚C = 310 KBody temp = 37 ˚C = 310 K Liquid nitrogen = -196 ˚C = 77 KLiquid nitrogen = -196 ˚C = 77 K

DENSITY Density is an INTENSIVE property of matter. Density is an INTENSIVE property of matter. does NOT depend on quantity of matter. does NOT depend on quantity of matter. temperature temperature Contrast with EXTENSIVE Contrast with EXTENSIVE depends on quantity of matter. depends on quantity of matter. mass and volume (separately). mass and volume (separately). Styrofoam Brick

Densities of Substances in g/cm 3 Aluminum 2.7Steel 8.1 Brass 8.7Titanium 4.5 Copper 8.3 Uranium 18.7 Gold 19.3Iron 7.8 Lead 11.3Water 1.0 Magnesium 1.7Zinc 7.1 LAB: Density of Solids and Liquids; Measurements and Significant Figures INQUIRY LAB: Density of a Grain of Sand

PROBLEM SOLVING Identify Question Draw a Picture or Model Identify Knowns List Useful Formulas and Equalities Convert Units to Match Each Other Use Formulas to Find Unknowns Until you reach the answer to your question

Stating a Problem Collecting Observations Scientific Methods

Searching for Scientific Laws Forming Hypotheses Forming Theories Modifying Theories

Substance Element Compound NaFeO2O2 NeonGoldCarbonH2H2 NaClFe 2 O 3 H2OH2O Baking soda Sugar Mixture Heterogeneous mixture Homogeneous mixture Chicken soup Italian dressing granite Sea water Kool Aid Grape juice paintbronze Stainless steel

PHYSICAL PROPERTIES What can you observe WITHOUT CHANGING what it is? MassSizeMagnetism VolumeShapeSolubility ColorTemperature OdorMP, BP Malleability, ductility

CHEMICAL PROPERTIES What observations can you make by CHANGING what it is? Reactivity (with another substance) Corrosability Flammability

In each case, decide if the change is a chemical or physical change. A cup of household bleach changes the color of your socks from red to pink Water vapor in your exhaled breath condenses in the air on a cold day Plants use carbon dioxide from the air to make sugar Chocolate melts when placed in the sun

Physical Changes and Separating Mixtures Mixtures retain the properties of the original substances, therefore, mixtures can be separated by differences in physical properties of the components of the mixture INQUIRY LAB: Separate and Collect Substances from a Mixture