8/26/10
Post date: Aug 25, 2010 8:31:36 PM
Bell Ringer: What is an element? What is a compound?
Molecule - two or more atoms that are bonded together
Matter is classified as either an element, a compound, or a mixture
Elements - made of only one kind of atom
The types of building blocks we have
Clay - different colors are different elements
The periodic table arranges elements by the properties of their atoms
Number represents number of protons
Mass is protons and neutrons, electrons have VERY little mass
Examples - Copper wire made of only copper atoms, aluminum foil made of only aluminum atoms
Social example - all men or all women together in a room
Compounds - made of two or more types of atoms
2 or more elements bonded together, and cannot be separated
Clay - multiple colors blended together
Examples - water is hydrogen and oxygen, table salt is sodium and chlorine, sugar is hydrogen, oxygen, and carbon
We use chemical formulas to represent formulas
Use element symbol from periodic table
Use numbers to note how many of each atom we have bonded together
Social example - two married people (different types of people, bonded together)
Mixtures - Elements and/or compounds are mixed together, but could be separated again
Clay - little balls of different colors together, but not mashed up so you could separate them out
Elements and compounds are pure substances, meaning their is a fixed ratio of components. Mixtures are not pure substances, meaning you could have any ratio of components in the mixture.
The parts of mixtures are not bonded together, and can be separated
Can be solid in solid, liquid in liquid, gas in gas, or combinations.
Social example - non-couples in a room together, or couples in a room with other couples or with single people
Analogy assignment (due 8/27/10)
Make (and write down) an analogy for element, compound, and mixture
Your analogy should compare the relationship between these three types of matter to relationships you're more familiar with
The notes labeled "Social example" are an example of an analogy for element, mixture, and compound.
OR come up with a mnemonic device