Organic Chemistry making plastic experiment

Carbon is the most remarkable of all elements. Its unique atomic structure enables it to link atoms together in long chains or rings in countless ways - so many that there is a whole field of chemistry, called "organic" chemistry, devoted to studying compounds of carbon. Every living organism, from lichens to people, is made from carbon compounds. Many carbon compounds are made with hydrogen only, but there are millions of them. These "hydrocarbons" include all the world's fossil fuels - coal, oil gasoline, gas - fuels formed from the carbon of dead vegetation around 300 million years ago. Other carbon chemicals, such as alcohols and sugars, include oxygen. The largest and most complicated carbon molecules of all are "polymers," from which plastics and many other man-made materials are made.

Making Plastic Experiment

Most plastics are man-made from oil and natural gas. But you can make your own very simple plastic from casein, the curds in mild, and set it in a mold to make your own plastic ornament.

Things you will need:

Muslin, Jars, Milk, Vinegar, Spoon, Saucepan, Rubberband, and Heater.

1. Warm 10 FL oz (0.3 liters) of milk in a pan, but do not boil. Add a tablespoon of vinegar and stir in.

2. A white, rubbery material, the casein, forms in the milk. Strain it off through muslin held over a container.

3. Squeeze the milk through the muslin until you have recovered all of the solid rubbery casein.

4. Push the casein into a suitable mold, such as a cookies cutter, or shape it by hand. Then leave it to set. 

Over a few days, the casein will gradually dry out and harden as the protein molecules bond tightly together. You can speed the process by leaving it on a warm radiator. If you wish to make a brooch, push a safety pin into the back while it is still soft. Once it has set paint it in your own design.

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Rock and Dissolved

Can something as soft as rain dissolve something as strong as a rock? You can find out in this science experiment. 

Things you will need:

Three cup drinking glasses
Lemon juice
Vinegar
Water
3 pieces of chalk

1. Pour 1/2 glass lemon juice into glass 1. Pour 1/2 glass vinegar into glass 2, and pour 1/2 glass water into glass three

2. Put 1 piece of chalk into each of the glasses. Make sure part of the chalk is in the liquid.

3. Place the glasses where they won't be knocked over.

4. Check on the glasses over the next few days. What is happening?

The chalk dissolves in the vinegar and in the lemon juice. When humans release carbon dioxide in the air, it dissolves into raindrops and makes rain become naturally acidic. Over time, rainfall which can dissolve and erode rocks. The chalk you used in the experiment is made of the rock limestone or calcium carbonate. When acids react with limestone, they eat away at the rock and start to break it apart. Lemon juice and vinegar are acids. They are much stronger than acid rain, so erosion happens more quickly. You can see how acid rain can affect rocks over hundreds and thousands of years.

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Melting point experiment

Rock is solid, water is liquid, and air is gas - but they do not have to be. Every substance in the world is a solid, liquid, or a gas, yet, given the right conditions, each can change into any of these "states of matter": solid, liquid, or gas. Even rock melts to liquid lava in the heat of a volcano; water freezes solid on very cold nights. It all has to do with the tiny particles - atoms and molecule - that make up every substance. In a slid, the particles are tightly knit together, like the bricks in a wall. So solids are fairly rigid and tend to keep their shape. You can pick up many solids but not water. When the solid gets hot, however, the bonds between the particles begin to break up and solid the melts to a liquid.

Besides heat, pressure can also melt solid, as this simple experiment shows. Hang a weighted wire over an ice cube. The wire cuts slowly through the cube as the pressure melt the ice.

Melting Point Experiment

Measure the melting point of different substances - the temperature at which a solid turns to a liquid. (Adult supervision is advised)

Things you will need:

Heater

Thermometer

Test tube

Heatproof jug or pan

Test solid (butter, chocolate, Jello, wax, etc)

How to do it:

Hold a test tube containing a small quantity of the test solid. Heat the water slowly in the jug or pan. Keep shaking the tube gently. As soon as the solid begins to melt remove the tube from the water and check the temperature. Repeat the experiment twice for each solid. Beware the test tube can get quite hot. If you can, hold it with a cloth or barbecue tongs.

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The bouncing egg experiment

Things you will need:

Eggs

Water

Vinegar

Flashlight

A bowl

1. Put 1 whole raw egg in a glass of water

2. Put 1 whole raw egg in a glass of vinegar

3. The eggs are the same, aren't they? Now, leave them for a few hours.

4. Look at both eggs. Do they still look the same? The egg in the water is the same, but the egg in the vinegar has changed. The shell has begun to fizz. The acid in the vinegar dissolves the calcium carbonate that is in the shell.

5. Look carefully. Does the egg in vinegar still have its shell? Touch it. It no feels and looks like a rubber ball, doesn't it?

6. Leave both eggs alone for 7 days. After that time, take the egg in the vinegar to a dark room and shine a flashlight at it. What do you see? The light bounces off the egg, doesn't it?

7. Take the egg out of the glass of vinegar. Hold the egg a little bit over a bowl.

8. Let the egg drop. Do you think it will splatter? Try it.

What happens:

Your egg bounces! Try it again getting a little higher each time. See how high you can make the egg bounce. What do you think will happen if you try to bounce the egg that was in the water? Hold it over the bowl and try.

Why:

• A chemical change takes place in the egg when left in vinegar.
• The vinegar, which is an acid, reacts with the calcium carbonate of the eggshell.
• The change makes the shell go soft, then disappear. This is called "decalcification".
• The egg in the glass of water does not chemically change.

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Measuring density lab experiment

When scientists talk about how much something weighs, they usually talk about its mass rather than its weight. Scientifically, you should use the word weight only when talking about the force gravity exerts on a particular object. So density is not the weight bust the mass of 1 cubic centimeter of the substance. Water, for instance, has a density of 1 gram per cubic centimeter. Gases are very light and have low densities - water is almost 1,000 times as dense as air. Most solids, however, are much denser than water. Gold, for example, is almost 20 times as dense as water.

A block of iron weighs more than a block of wood the same size, iron is said to be denser than wood. Every substance has its own density, which is how much a certain amount of it weighs. This experiment shows how to work out the density of different solid. 

Thins you will need:

1. A plastic bottle

2. A measuring cup

3. A knife

4. A scale

5. Some graph papers

6. A plastic tube

Instruction

1. Cut the top off a plastic bottle, make a hole a little way down, and fix the tube in with modeling clay, making the seal as watertight as you can

2. Put a container under the spout, and fill the bottle with water until it pours out of the spout. Now select the object to be measured

3. Place an empty measuring cup under the spout, and immerse the object fully in the bottle. Note how much water spills into the cup.

4. Take the object from the water, dry it, and weigh it. To calculate the density, divide the weight by the volume of water in the cup.

5. Your project should look similar to the picture below when done.

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Uniform Motion along a Straight Line

This represents an important situation. In this case, the acceleration vector is constant and lies along the line of the displacement vector, so that the directions of v and a can be specified with plus and minus signs. If we represent the displacement by s (positive) if in the positive direction, and negative if in the negative direction), then the motion can be described with the five equations for the uniformly accelerated motion:

Direction is important, and a positive direction must be chosen when analyzing motion along a line. Either direction may be chosen as positive. If a displacement, velocity, or acceleration is in the opposite direction, it must be taken as negative.

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Uniformly Accelerated Motion

Speed is a scalar quantity. If an object takes a time interval t to travel a distance d, then average speed is equal to the total distance traveled divided by time taken:

Or

Here the distance is the total (along the path) length traveled. Velocity is a vector quantity. If an object undergoes a vector displacement, s, in a time interval, t, then average velocity is equal to vector displacement divided by time

Or 

The direction of the velocity vector is the same as that of the displacement vector. The units of velocity (and speed) are those of distance divided by time, such as m/s or km/h.

Acceleration also a vector quantity, measures the time-rate-of-change of velocity:

Where Vi is the initial velocity, Vf, is the final velocity, and t is the time interval over which the change occurred. The units of acceleration are those of velocity divided by time. A typical example is (m/s)/s or ms^2 )

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Parallelogram Method for Vector Addition and Subtraction

Parallelogram Method for Vector Addition 

The resultant of two vectors acting on any angle may be represented by the diagonal of a parallelogram. The two vectors are drawn as the sides of the parallelogram and the resultant is its diagonal, as shown below. The direction of the resultant is away from the origin of the two vectors.

Component Method for Vector Addition

Each vector is resolved into its x-, y-, and z-components, with negatively directed components taken as negative. The scalar x-component, Rx, of resultant R is the algebraic sum of all the scalar components. The scalar y- and z-components of the resultant are found in a similar way. With components know, the magnitude for the resultant is given by

In two dimensions, the angle of the resultant with the x-axis can be found from the relation

Vector Subtraction

To subtract a vector B from a vector A, reverse the direction of B and add individually to vector A, that is 

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Graphical Addition of Vectors (Polygon Method)

Note: Whenever you see A, B, C or R in a sentence that means I am referring to the symbols below

This method for finding the resultant R of several vectors

(A, B, C consists in the beginning at any convenient point and drawing (to scale and in the proper directions) each vector arrow in turn. They may be taken in order of succession.

The tail end of each arrow is positioned at the tip end of the preceding one, as shown below.

The resultant is represented by an arrow with its tail end at the starting point and its tip end at the tip of the last vector added. If R is the resultant, R = |R| is the size or magnitude of the resultant.

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Scalars and Vectors

Please note that whenever I mentioned i j and k in a sentence I am referring to the special unit vectors: .

A scalar is a quantity that possesses only magnitude. Some example of scalar quantities includes mass, length, time, distance, speed, and density.

A vector is a quantity that possesses both magnitude and direction. Examples of vector quantities are displacement, velocity, acceleration, and force. A vector quantity can be represented by an arrow drawn to scale. The length of the arrow is proportional to the magnitude of the vector quantity. The direction of the arrow represents the direction of the vector quantity.

The Components of a Vector

Before we define the components of a vector, we first must introduce the elementary relationships between trigonometric functions. The trigonometric functions are defined in relation to a right angle. For the right triangle shown below by definition.

We often use these in the forms

             

A component of a vector is its effective value in a given direction. For example, the x-component of displacement is the displacement parallel to the x-axis caused by the given displacement. A vector in three dimensions may be considered as the resultant of its component vectors resolved along with any three mutually perpendicular directions. Similarly, a vector in two dimensions may be resolved into two component vectors acting along any two mutually perpendicular directions. The picture below shows the vector R and its x and y vector components, Rx, Ry, which have magnitudes

Unit Vectors

Unit vectors have a magnitude of one and are represented by a boldface symbol topped with a caret. The special unit vector (see below) are assigned to the x-, y-, and x-axes, respectively. A vector 3 i represents a three-unit vector in the +x direction, while -5 k represents a five-unit vector in the -z direction.

A vector R that has scalar x-, y-, and x-components Rx, Ry, and Rz, respectively, can be written as 

When an object moves from one point in space to another, the displacement is the vector from the initial location to the final location. It is independent of the actual distance traveled.

Vector Addition

The resultant, or sum, of a number of vectors of a particular type (force vectors, for example) is that single vector that would have the same effect as all the original vectors taken together.

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Using intercepts and symmetry to sketch a graph

Problem	Solution
	Symmetry: None
	Symmetry: None

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