Sodium Bicarbonate, Calcium Chloride and Phenol Red

Let’s go over the procedure first and then we will discuss what is happening.

1. In a quart baggie, place sodium bicarbonate(1 tsp) in one corner and calcium chloride(1 tsp) in the other.
2. Lay the bag on its side and place a small cup (medicine cup size – 1 oz) of phenol red in center of the bag. Be careful not allow the any on the chemicals to mix yet. Seal the bag
3. Gently pour the phenol red where it spills into each corner. Do not mix the two corners yet.
4. Have the students feel each corner and make observations. Continue the observations for a few minutes.
5. Pick the bag up and gently move the bage side to side, mixing the chemicals. What happens?

Explanation

The side of the bag with calcium chloride becomes warm. The calcium chloride dissolves forming calcium and chloride ions. The release of heat (exothermic) is a result of the calcium chloride dissolving and not a chemical reaction.

When the sodium bicarbonate dissolves to form sodium, hydrogen and carbonate. It becomes cool (endothermic). The baking soda absorbs heat in order to dissolve. This is not a chemical change.

When the two sides are mixed, calcium carbonate is formed which is insoluble. Also formed are water and carbon dioxide. The carbon dioxide (gas) causes the bag to inflate. When the carbon dioxide dissolves in the liquid, carbonic acid is formed. This change in pH causes the phenol red to turn yellow. A chemical change has now occurred.

Remember to have the students use all lab safety measures. If the bag becomes over inflated, release some of the gas.

The reason for the growth is partially associated with new government regulations concerning our impact on the environment. Federal and local governments are receiving pressure from voters to find alternative sources. Experts believe that if the 2030 scenerio occurs, we would reduce carbon dioxide emissions by 7600 metric tons and create 200,000 jobs.

Windmills have been around for centuries to pump water and grind seeds into grain. A wind turbine is an advancement that turns an electrical generator. The force of the wind, turns the blades. the rotor turns and spins a driveshaft that is connected to an generator. the generator converts this mechanical energy in to electrical energy.

There are several variables that determine the amount of energy produced: wind speed, diameter of the rotor, density of the air, and efficiency of the turbine.

A great product for teaching wind power concepts is the Basic Turbine. The Basic Turbine is a great start for teaching about wind energy in the classroom. Visit www.heathscientific.net to purchase this item. This is the most affordable and robust wind turbine kit on the market. Design blades and test your power output with a multimeter, LED bulbs, or an ultra capacitor.

The instructions that are included will show you how to build this PVC turbine, how to make blades for your wind turbine, how to use a multimeter to record electrical data and will discuss some basic wind energy science.

In School Science Store

When approached properly, science is easy to make interesting……but it isn’t free. The students benefit greatly from using real science equipment, beakers….graduated cylinders…microscopes….live animals…pipets and test tubes. As educators, one goal should be to create young scientists and prepare them for the world they will find.

I often hear that “My school can’t afford these items.” With some hard work, outfitting a science lab can be achieved. Heath Scientific has been providing fundraising options to teachers, PTO’s and school organizations for 10 years. Create excitement and interest in your science program by setting up an Exploration Fair. Your school will ask volunteers (parents are great resources) to help run a retail store for a week. The store has science experiments, rocks, fossils and educational toys that excite the students and raise funds for your school.

Set up an online store at www.sciencefundraiser.com and encourage students and parents to visit the site for birthday and christmas presents or for science fair projects. The items are shipped directly to the customer and you do not have to distribute any merchandise. Your organization receives a percentage of all sales.

Heath Scientific also provides bulk packages that allows your organization to make up to 80% profits. Use the profits earned to buy real science equipment that can be used for many years.

Don’t let money stop you from providing your students a top notch science classroom.

Glacial Heat

What’s Happening?

Inside the Glacial Heat, exists a supersaturated and super-cooled (below it’s freezing point) solution of sodium acetate and water. This supersaturated solution was created by mixing the salt (sodium acetate) in hot water. Hot liquid will dissolve more salt than a cold one. When this solution is cooled slowly, the salt stays in solution.

A small, stainless steel, metal chip provides the “spark”. When the chip is squeezed, a small, single, solid salt molecule is created. This is the seed ,on which, the other salt crystals begin to form. The normal freezing point for sodium acetate is 130 degrees F (54 degrees C). The reaction occurs quickly, with heat being released and the liquid becomes solid (freezes). The heat being released is equal to the freezing point of the solution (54 degrees C). The sodium acetate (a salt) dissolving and freezing in the water is an example of a physical change.

How do I Teach With Glacial Heat?

Discuss physical and chemical properties:

Physical properties are observable (color, size, luster and smell) and also include characteristics, such as, freezing point, melting point, malleability, conductivity, volume, mass, weight and length.

Chemical properties are only observable during a chemical reaction and can include flammability or the ability to rust. In each of these examples, a new compound has been formed.

Discuss physical and chemical changes:

Physical changes include ice melting, molding clay, water evaporating, a coke freezing and sugar dissolving in water. In these examples, no chemical changes have occurred and the changes can be reversed.

Chemical changes include metal rusting, lighting a match, milk souring and the stomach digesting food. These changes are not easily reversed. The presence of light, color change, odor, gas production, heat or sound can indicate that a chemical change has taken place.

The Glacial Heat can be boiled (melted) for 7-10 minutes and reused over and over again.

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.

Solar Science Kit

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.

How Does Nitrogen Enter the Soil?

Before nitrogen can be used by plants, it must enter the soil. Atmospheric nitrogen is forced to the ground by rainfall. Also, urine, solid and liquid waste from living organisms and living organisms that have died are deomposed by bacteria and fungi. The nitrogen from these sources then enter the soil. Commercial fertilizers are another source of nitrogen.

What Happens to Nitrogen in the Soil?

Plants cannot use organic nitrogen. Bacteria and fungi are needed to transform this unusable organic nitrogen into a usable form. Although most nitrogen fixation is completed by bacteria, some is accomplished through lightning strikes. Since ammonia is fatal to most plants, bacteria convert this ammonia (NH4) into nitrates (NO3) and nitrites (NO2). At this time, the nitrogen can be assimilated into the plant, leached into the ground water or be transformed into a gas and re-enter the air.

In very wet soils, the oxygen content is low. The bacteria in these soils take the oxygen out of the nitrates (NO3) and produce nitrogen gas. This process is call denitrification. Through a process called volatilization, the gas re-enters the atmosphere.

Dissecting

What is an Owl Pellet?

An owl pellet is the portion of an owl’s prey that has not been digested. Owl’s swallow their prey whole (they don’t have teeth to chew) and the feather’s, fur, bones and other undigestible parts are regurgitated by the owl.

How Does the Owl Pellet Form?

When the prey is swallowed, it travels through the esophagus and into the first part of the stomach, the proventriculus. Unlike other birds, the owl does not have a crop to store the food. As a result, the prey enters directly into the digestive tract. This part of the stomach has enzymes and acids (like our stomachs) to aid in digestion. From the proventriculus, the food travels to the second part of the stomach, the gizzard. The gizzard is a muscular organ that grinds the food and “filters” undigestible parts from traveling into the intestines.

The pellet is formed from the hair, bones or feathers that are left in the gizzard. The pellet will take several hours to form and several more before it is regurgitated. The owl cannot eat again until this pellet is expelled.

Does the Regurgitation of the Pellet Benefit the Owl?

Yes. Many scientists believe that this regurgitation of the pellet keeps the upper digestive tract clean.

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?)