1. Materials: wire, batteries, bulbs, and switch. Procedure:
Name: __________________________ Date: ______ CP: _____ Series Circuits
Prediction: What are the advantages and disadvantages of a series circuit.
Materials: wire, batteries, bulbs, and switch.
Procedure:
Create a series circuit with one bulb.
Create a series circuit with two bulbs and a switch. Open and close the switch and observe what happens.
Observation:
Draw a picture of the series circuit you made with two bulbs. Be sure to label the load, battery, and switch.
What happened to brightness of the original bulb when you added a second bulb to the series circuit? Why?
What happened to the bulbs when you opened and closed the switch for the series circuit? Why?
Explain:
1. What are two advantages of a series circuit?
2. What are two disadvantages of a series circuit?

2. Materials: wire, batteries, bulbs, and switch. Procedure:
Name: __________________________ Date: ______ CP: _____ Parallel Circuits
Prediction: What are the advantages and disadvantages of a parallel circuit.
Materials: wire, batteries, bulbs, and switch.
Procedure:
Create a parallel circuit with two bulbs, so that one bulb turns off and the other stays lit when a switch is open.
Add an additional pathway with a bulb to your parallel circuit.
Add a second bulb to one of the pathways.
Observation:
Draw a picture of the parallel circuit you made with two bulbs. Be sure to label the load, battery, and switch.
In procedure #2, how was one bulb able to stay lit and the other was not?
What happened to the bulbs in the original pathways when you added an additional pathway and bulb to the parallel circuit? Why?
What happened to the original bulb when you added a second bulb in the same pathway? Why did this happen?
Conclusion:
5. What are two advantages of a parallel circuit?
What are two disadvantages of a parallel circuit?

3. Battery Reactions and Chemistry
A lot happens inside a battery when you pop it into your flashlight, remote control or other wire-free device. While the processes by which they produce electricity differ slightly from battery to battery, the basic idea remains the same.
When a load completes the circuit between the two terminals, the battery produces electricity through a series of electromagnetic reactions between the anode, cathode and electrolyte. The anode experiences an oxidation reaction in which two or more ions (electrically charged atoms or molecules) from the electrolyte combine with the anode, producing a compound and releasing one or more electrons. At the same time, the cathode goes through a reduction reaction in which the cathode substance, ions and free electrons also combine to form compounds. While this action may sound complicated, it's actually very simple: The reaction in the anode creates electrons, and the reaction in the cathode absorbs them. The net product is electricity. The battery will continue to produce electricity until one or both of the electrodes run out of the substance necessary for the reactions to occur.
Modern batteries use a variety of chemicals to power their reactions. Common battery chemistries include:
Zinc-carbon battery: The zinc-carbon chemistry is common in many inexpensive AAA, AA, C and D dry cell batteries. The anode is zinc, the cathode is manganese dioxide, and the electrolyte is ammonium chloride or zinc chloride.
Alkaline battery: This chemistry is also common in AA, C and D dry cell batteries. The cathode is composed of a manganese dioxide mixture, while the anode is a zinc powder. It gets its name from the potassium hydroxide electrolyte, which is an alkaline substance.
Lithium-ion battery (rechargeable): Lithium chemistry is often used in high-performance devices, such as cell phones, digital cameras and even electric cars. A variety of substances are used in lithium batteries, but a common combination is a lithium cobalt oxide cathode and a carbon anode.
Lead-acid battery (rechargeable): This is the chemistry used in a typical car battery. The electrodes are usually made of lead dioxide and metallic lead, while the electrolyte is a sulfuric acid solution.
The best way to understand these reactions is to see them for yourself. Go to the next page for some hands-on battery experiments.