Last Night’s HW Any questions…?

Warm Up: Mystery Powder You walk into the kitchen and find a white powder on the counter. You don’t know what it is – it looks like baking soda, but it could be rat poison. You want to know what it is, but you don’t want to taste it. What could you do?

Properties of Matter Notes

Review… Matter: anything that has mass and takes up space Mass: the amount of matter in an object Volume: the amount of space an object takes up Density: mass per unit volume (how much stuff in a given space; how tightly packed the stuff is)

Mass, Volume, Density… 1. Which of these three properties changes depending on how much of it you have? 2. Which of these three properties does not change depending on how much of it you have?

Properties of Matter Two Types: Physical Properties Characteristic Properties

Physical Properties - Features that are true only for a certain amount of matter - Properties of an object Examples: - Mass - Smell - Texture - Volume - Temperature - State - Shape

Characteristic Properties - Features that DO NOT change as mass, volume, and/or shape change - Properties of a substance, not an object Examples: Density - Solubility Boiling point - Melting point

Characteristic Properties Freezing point: the temperature at which a substance changes from a liquid to a solid Examples of substances that change from liquid to solid (or solid to liquid):

Characteristic Properties Boiling point: the temperature at which a substance changes from a liquid to a gas Examples of substances that change from liquid to gas (or gas to liquid):

Big Idea! Because characteristic properties are not affected by physical changes, they can be used to identify matter! Think back to the white powder question… How could you figure out what it is?

Does salt water have different properties than fresh water? Similarly… We can compare a pure substance and a mixture. Does salt water have different properties than fresh water?

When it snows in Seattle Video Link

Why do we salt roads when it snows? Salting roads when it snows in Providence

Why do we salt roads when it snows? Consider: What does the salt do to the snow? Why?

Icy Hot Lab Objectives: Collect and graph temperature vs time data. Identify the melting and boiling points of a substance from a temperature vs time graph. First, make predictions!

Icy Hot Lab Group Jobs: Time Keeper (stop watch) Temperature taker (thermometer) 1 or 2 Data Recorders (keep careful data table)