The Carbon Cycle

Carbon is released into the environment in many ways. Animals and plants respire, releasing carbon dioxide into the atmosphere.  Animals release solid waste products into the soil and water. Also, leaves, roots, wood and dead animals decay. Finally, the burning of fossil fuels and wood release stored carbon into the atmosphere.

The carbon that is released into the environment, is used by many plants and animals. This is the part of the carbon cycle that removes carbon from the atmosphere. Plants and algae take in carbon dioxide during photosynthesis. Many sea creatures take in carbon when making shells and bones. When these animals die and sink to the ocean floor, this carbon is stored for some time.

The Ocean’s Role

The majority of photosynthesis  occurs in the oceans by algae and phytoplankton. Also, due to the large surface area of the oceans , carbon dioxide diffuses in and out in an attempt to equalize.

The dark color reduces the amount of photons reflected. Photons that are not absorbed by the panel cannot be used to produce electricity.

What are Photovoltaic Cells Made From?

Silicon is the major material in the cells. Pure silicon crystals are poor conductors of electricity. Other elements are added to the silicon, such as, phosphorus and boron. When the energy from the sun hits the cell, the electrons in the elements begin to move around. The sun causes the panel to have a positive and negative side. This electrical difference causes electrons to flow through a diode.

What Factors Affect the Production of a Solar Cell?

The factors that most affect the production of a solar cells are the angle of the panel in relation to the sun, the peak wattage, the light intensity and the hours of sun exposure.

How is Wattage (or Power) Calculated?

The formula for power is   Power=Current X Voltage. Power is measured in watts, current in amperes and voltage in volts.

The Solar Science Kit has a small motor, photovoltaic cell and disc that works well in demonstrating this in a classroom or home setting.

When a magnet moves toward a metal object, the electrons in the metal move. As a result, when a magnet moves near a copper wire, electrons in the copper move. Generators use this principle to convert mechanical energy (the rotation of a wire coil,or rotor around a magnet) into an electrical current (electrons flowing through the wire). A motor performs the opposite function by converting electrical energy into mechanical energy. For the most part, all generators work the same. The item that separates them is, “What turns the rotor?”

Windmill Generator Kit

 Energy Conversion in a Windmill 

 Obviously, in a windmill, the wind is rotating the wire coil around the magnet. This generator is taking the kinetic energy from the wind and converting it to electrical energy.

Windmills are rated based on output power (watts), working voltage (volts), start up windspeed (mph), survival wind speed (mph), rated rotation of the blades (rpm) and the diameter of the blades  (also called the rotor). In general, the larger the rotor diameter the more wind that is intercepted and the more electricity produced. There are do-it-yourself plans available for building your own windmill. No waste or pollution is produced during this process.

When discussing this in the classroom or entertaining your children on the weekend, there are some small demonstration kits available. The Windmill Generator from 4M Kidz Labz TM is an excellent activity.

See the Oxygen molecules bubble and the indicator turn pink

Hydrolysis Water Splitting
Using a 9V battery, 2 electrodes and small gauge wire, you can split water into its component parts. This process is called hydrolysis. We add a small amount of salt to increase the conductivity of the water and an acid/base indicator to visualize the reaction.

The chemical formula of water is H2O. When the electrical current, produced by the battery, passes through the water,  the water will split and the two electrodes will bubble. Hydrogen will appear at the cathode and the oxygen at the anode. The acid base indicator around the cathode will turn blue (because the free OH molecules raise the pH) and the area around the anode will turn pink (because the free hydrogen molecules lower the pH).

Looking at the formula for water, there are twice as many hydrogen atoms as oxygen. When hydrolysis occurs, twice as many hydrogen bubbles will be released as oxygen. You can visually see extra bubbles at the point where hydrogen is being released.

Hydrolysis experiments can be quantitative (how much hydrogen and oxygen are released?) or qualitative (can I visually see the reaction taking place?)

Other projects similar to the Hydro-Splitter are also available from the Heath Scientific website. The website offers science supplies as well as other science projects cover a wide range of topics from carbon to light and optics kits. These kits offer a cost effective way for parents to enrich their children’s minds while having fun at the same time.

General Information

Water is made up of twice as many hydrogen molecules as oxygen molecules; this is why the chemical formula is H2O. Electricity breaks this formula down when introduced into water. The molecules split with hydrogen appearing at the cathode and the oxygen will mix with one hydrogen molecule making hydroxide.

Supplies Needed

- 1 Beaker
- 2 Carbon Rod Electrodes
- 1 Acid/Base Indicator
- 3 Alligator Clip Wires
- Salt
- 2 Droppers
- 9 Volt Battery- not included in the Hydro-Splitter Kit

Experiment Procedure

The carbon rod electrodes are connected to the battery with the alligator clip wires. Fill the beaker with 200 milliliters of water along with 25 drops of acid/base indicator and a pinch of salt. Adding a second 9 Volt battery can increase the speed of the reaction.

Results

There will be more hydrogen molecules than oxygen in the water and the electrode that the hydrogen is drawn to will have more bubbles. The water around this electrode will be blue; the water around the other electrode where the oxygen is drawn will be pink. This kit allows for a cost effective way to explain the concepts of electricity and voltage.

Founded by Pat and Heath Nichols, Heath Scientific is a provider of educational supplies located in Cedar Hill, Texas. Major suppliers of Heath Scientific include AntWorks, Thames & Kosmos, Uncle Milton, and Can You Imagine. If you are interested in hosting a school fundraiser, or obtaining science related educational tools, contact Heath Nichols at Heath Scientific by email at heath@heathscientific.net or by phone at (972) 291-4223.