Unit 3 Study Guide

Cell 225-572-7298

You should know the following:

1. Most Metals have high luster, are malleable, and conduct heat and electricity very well

2. The difference between Physical and Chemical changes. The difference between them is best determined by the evidence.

Evidence of Physical Change: The type of matter DOES NOT CHANGE but there might be Changes of state, change of shape, changes in density, volume, or mass(size), and sometimes changes in color.

Evidence of Chemical Change: The type of matter afterwards DOES CHANGE into something different and some evidence is the Formation of a gas, Formation of a Precipitate, sometimes a change in color, and always a Change in energy (endothermic= absorbs heat & feels cooler, exothermic= releases heat & feels warmer)

3. In a chemical equation REACTANTS react or combine or break apart to yield PRODUCTS which are a completely different material

4. Chemical equations must show the SAME number and kind of atoms on each side of the equation. The mass of each side must be the same

5. What factors (kinds) of things affect the rate of a chemical reaction:

A) Temperature: high temperature = faster reaction
lower temperature = slower reaction

B) Concentration: high concentration of reactants = faster reaction
low concentration = slower reaction

C) Surface Area: more surface area (like a powder) = faster reaction
less surface area (chunk) = slower reaction

D) Catalysts: speed up a reaction

E) Inhibitors: slow down a reaction

F) Pressure: higher pressure = faster reaction
lower pressure = slower reaction

Oh, and that experiment that we didn't do in class but

I described to you is here,

just click here.

Remember, the copper sulphate solution turns clear, the iron nail gets a copper coating and copper color, and the solution feels warm.

You'll be asked to list what evidence there is that a chemical change occurred and you'll need to explain what type of chemical reaction (endothermic or exothermic) happened.