Class Blog 10/09/13

Class Blog 10/09/13

Beginning of Class

1. Check in homework

• Word Equations
• Balancing Chemical Equations
• Section 3.4 Notes

2. Pick up Handouts

• Six sheets total
  3. Go over homework, answer any questions
  4. Pop Quiz on balancing chemical equations

  Balance MgSO4 + NH4OH → (NH4)2SO4  + Mg(OH)2

  
  

  MgSO4 + 2NH4OH → (NH4)2SO4  + Mg(OH)2

Notes

1. Combination Reaction

• A + B → AB
• Two elements combine to make a compound

2.Decomposition Reaction

• AB → A + B
• A compound breaks up into simple elements

3.Combustion Reaction

• CxHy + O2 → CO2 + H2O
• A compound made of H and C reacts with O2 to make CO2  and H2O

4.Single Replacement Reactions

• A + BC → B + AC
• If the element is a metal it replaces the metal (positive) ion
• If the element is a nonmetal it replaces the nonmetal (negative) ion
• Places only get replaced if the single element is higher up on the Activity Series Chart  than the element in the compound

5.Double Replacement Reactions

• AB + CD → CB + AD
• Activity Series Chart is not used in this
• Two ionic compounds trade positive (front) ions
  
  
  
  
  
  

The next scribe is Dorothy W.

Class Notes 8/27/13

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• Grab handouts on variables and experimental design and on substances from the table.

Questions of the Day

• What did you think of the observation lab? What did you learn from it?
• What were the three kinds of variables we talked about yesterday?
• How do chemists classify matter?

Reactions to the Observation Lab

• “It was very interesting”

• “It was a lot of fun”
• Purpose was to learn about how experiments are to be done in this class and  to learn about the experimental process

Review of Variables

“Independent Variable

• What I change (As experimenter)

Dependent Variable

• Data
• What I observe and measure
• Qualitative Observations
• No numbers
• Quantitative Observations
• Has numbers and measurements

Controlled Variable

• Everything you try to keep the same from trial to trial”

- Danny Shiller

Classifying Matter

Pure Substances

Elements

• 110 of these.
• Can’t be broken down.
• All atoms of an element are identical.

Compounds

• Different elements that are combined chemically

Mixtures

Homogeneous

• Same throughout

Heterogeneous

• Different throughout

The next scribe is Allie Boland