Quiz Review

For next week's quiz be sure you can draw and label the parts of the atom (and their charges), know how to apply the Density formulas, be able to provide examples of homogeneous and heterogeneous mixtures. Also be able to do everything that was on your last quiz, (but without referring to the periodic table.)

Elements and Compounds

Elements are made up of 1 type of atom.

Compounds are made of 2 or more elements that are chemically bonded. Example: Water is a compound that contains the elements hydrogen and oxygen. The hydrogen and oxygen atoms are chemically bonded into a molecule of water.

Molecules are two or more atoms that are chemically bonded. Sometimes the atoms in a molecule are the same element.

The differences between mixtures and compounds.
Mixtures can be made or separated by physical means.
Compounds can only be made or separated by a chemical reaction. They cannot be separated by physical means only.

Pure substances can be an element or a compound. They are always homogenous. Every molecule or atom throughout the substance will be the same.

Pure substances can be elements or compounds.

Mixtures
Mixtures can be of elements, compounds or both.
Mixtures can be
-homogeneous (Ex. water and alchohol)
-heterogeneous (Ex. oil and water)
Mixtures can be solid, liquid, or gas.

Lab
copper sulfate and sulfur
The problem: When copper sulfate, sulfur and water are mixed does a chemical reaction occur?

October 9 Density Formulas

The formula for density is density = mass/volume D=M/V
This means that mass=density times volume M=DV
and Volume=Mass divided by density V=M/D

So when you are given two of the measurements, and asked to find the third use the above formulas.

October 8, Periodic table organization

Orginization of periodic table
Periods-Horizontal
Groups-vertical

Group 1-alkali metals, most reactive metals, lose 1 electron in reactions
Group 2-alkaline earth metals, less reactive than group 1 but still reactive, lose 2 electrons in reactions.
Group 17-most reactive not metals, gain 1 electron in reactions
Group 18-noble gases, non-reactive

Elements you should recognize
Na, K, Pb, Au, Ag, Fe, and Sn

You should be able to determine the number of protons, neutrons and electrons in an atom by reading the periodic table.

Be able to describe the different properties of metals, transition metals, metalloids, non-metals and rare earth metals and to be able to roughly map them on the periodic table.
Notebooks will be collected Wednesday, October 10.

First Post

Hi, everybody,

Look here to find what's been covered recently in your science class. Anything you find here will likely be on the tests. Look here to see what you can do to catch up and complete entries in your Science Notebook to make up what you missed. You can use comments to ask questions about class work. Remember that comments should be relevant to the class. Please use proper written English, including grammar and punctuation--do not use text messaging or IM-speak, because I don't use it and because it is inappropriate for school work. Any comments will be respectful, and will be monitored before posting.