Unit 6: Chemistry (Interactions of Matter)Chapter 13 -- Chemical Bonding (electrons and chemical bonding / ionic bonds / covalent and metallic bonds)
Chapter 14 -- Chemical Reactions (forming new substances / chemical formulas and equations / types of chemical reactions / energy and rates of chemical reactions)
Chapter 15 -- Chemical Compounds (ionic and covalent compounds / acids and bases / solutions of acids and bases / organic compounds)
Resources:
Activity for 2/29/2012: Exploring Acids, Bases, and an Indicator
Overview: In this activity you will be exploring (predicting, testing, and researching) the acid-base levels of various household chemicals.
Materials (per group): - 8 clear plastic cups
- Supply of vinegar, M.o.M, ammonia, OxyClean, baking soda, lemon juice, apple juice, shampoo
Cautions: - Do not mix the chemicals with each other unless I tell you to.
The drain cleaner, for example, will react with the ammonia to produce a dangerous gas. - Avoid skin and eye contact with any of the chemicals and don't taste or inhale their fumes unless instructed.
- Move carefully and speak quietly -- this is a crowded room.
Procedure: - I will demonstrate the effect of the cabbage indicator reaction with a base and an acid. (like this)
- Get into 7 groups of 4 or 5 at a table and name yourselves (one word).
- One person gets 8 clear plastic cups and two permanent markers. Bring back to table
- Label the cups with group name and name of a chemical listed above -- one color for (predicted) bases and one color for acids
- One person brings the cups back to the supply table and line them up to get samples of each chemical from me
- Once filled, the runner brings the cups back to the table two at a time. Don't sniff the ammonia... waft instead.
- Put your samples in (predicted) order from most acidic to most basic.
- One person come get a cup of cabbage-juice indicator and 6 more empty cups. No spills or clothes stains please!
- Distribute the indicator between the 8 empty cups
- Choose one sample and slowly add enough chemical to the indicator to attain a color change.
- Repeat step 10 for each sample.
- Compare your colors with other adjacent tables
- Now, try to predict the actual pH number for each fluid
- Go online and find the actual (or range of) pH for each fluid.
- Discuss your predictions, process, and results with me
- Combine an acid and a base (just one of each), observe the reaction, and try to attain neutrality -- test with the indicator
- Bring cups to sink (do not nest them) and rinse them under low-flowing faucet.
- Put empty cups into tub provided and wipe table if necessary
- Use the simulation linked below to learn more about acids and bases
| Click to Run the Ph Simulator Above |
Making Molecule Models with Marshmallows and Toothpicks
Using marshmallows represent atoms and toothpicks represent covalent bonds, you will research, diagram, and assemble various organic compounds.
Carbon atoms are black and need four bonds
Hydrogen atoms are white and need one bond
Oxygen atoms are red and need 2 bonds
Procedure
- Get into pairs (4 pairs at each double-table)
- Get a supply of marshmallows and toothpicks
- Choose a molecule (start simple)
- On paper, draw the molecule model and check for proper bond numbers for each atom
- Confirm or revise by doing online research
- Build the model using marshmallows and toothpicks. Label it (labels provided) with your names and name of molecule
- Get confirmation from the others at your group and the teacher
- Repeat steps 3 to 7 as time, materials, and motivation provide
- Try to have each molecule built per group, and no more than 3 of any one molecule.
Molecules:
a. O2
b. C3H8
c. C4H10
d. chris, finish this and make subscripts |
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