Sugar Crystals

During my holiday, I spend some of my time building a sugar crystal. After this experiment, I realised that making sugar crystals was not as easy as it looks.

I made a few different experiments, before finally coming to some of the details. I used 1 jar of water to 3 jar of sugar. This is to allow the sugar solution to be saturated.

Materials

As follows are the steps:

1. Pour in the jar of water into a pot.
2. Heat up the pot. Wait for the water to start to boil.
3. Start to pour the sugar slowly into the pot while stirring.
4. After all the sugar was poured, turn off the gas.
5. Pour the solution into a Jar.
6. Put a string into a Jar. 

The string that I used was covered with a some sugar, which acts as the seed crystal to encourage growth of my sugar crystal.

As follows are a few video of parts of my experiment.

In this video, I pour the sugar and stir the solution.

Here, I poured the solution into the jar.

This video is a short, showing me putting the string into the jar. I put the string into the jar. I had to make sure that the string did not touch the sides.

Not only this "Perfect" Solution, I had also come up with a few other set-ups to see which one works the best. One, is the solution, where I had covered the jar containing the solution. The sugar crystals did not form that lot as compared to the set up with the jar open. 

The sugar crystal in the bottle without cover

However, the bottle which was uncovered gave better results.

Crystals from uncovered Bottle (1)

Crystals from uncovered Bottle (2)

The Original Bottle was like that, with the bottle filled with 1 crystal.

I could not lift the crystal by the string! However, I was quite sure that was 1 crystal. Then, I decided to break the vase so that at least a crystal can come out. Yes, it did. However, it was broken. The biggest piece was 79.5g, far away from the top crystal (as of my writing) at 287g. 3 times! I believe that that person must have used a big bottle to come up with such an large one. However, through this experiment, I realised how hard it was to come up with a sugar crystal like that, and how much effort was required to come up with one.

As follows are just some photos from my process of making crystals. :)

Left: Day 1    Right: Day 4
(Both bottles are meant to be uncovered)

Evaporation Set-up Starting

The many multiple crystals in the End of the evaporation set-up

Plasma and Bose-Einstein Condensate (BEC)

It all started when my teacher told me there are five states of matter.

We all know the three basic states of Matter: Solid, Liquid, and Gas. However, there are two other states: Plasma, and Bose-Einstein Condensate (BEC).

What are they?

First, I did the research on Plasma.

Plasma is like gases. However, the atoms are different, as they are made up of free electrons and ions of an element such as Neon (Ne). It is also made up of groups of positively and negatively charged particles. The particles are also free to move. There is practically no order, as compared to a gas.

Aurora Lights

Natural Plasmas do not occur very often. However, the Northern Lights and the Southern Lights, also known as aurora borealis and aurora australis respectively, is one example of Natural Plasma. It is caused by the collision of energetically charged particles with atoms at a high altitude within our atmosphere. Solar Winds that flow past Earth contains plasma particles which get pulled into the Earth's magnetic fields. Hence, aurora occurs both in the North and the South. Collisions also occur between the plasma particles, nitrogen, and oxygen atoms, releasing energy, which is the Northern and Southern Lights. 

Man-made Plasmas, however, happen in our surroundings. Take a look at the Fluorescent Light Bulbs placed in our homes. Inside these bulbs or tubes contain an inert gas, like argon. This gas is kept under low pressure, so that the plasma is easily formed. The electricity charges up the gas, which creates plasma. These uses lesser energy than Incandescent lamps, which is why it saves electricity.

Another example is the Plasma Ball. The Plasma Ball is actually made up of a coil of high current wires. The electrons, that is oscillating quickly, shakes the atoms, causing their electrons to fall of and form plasma. The Ball contains a partial vacuum, making it easier to make electric sparks that can be seen.

There are, of course, many other places where man-made plasma is found. Above are just a few examples.

Now, what about Bose-Einstein Condensate, also known as BEC for short?

Here is an video on Bose-Einstein Condensate.

Energy Change from BEC to Plasma

Bose-Einstein Condensate consists of unexcited and cold atoms, the exact opposite of that of Plasma. The state only happens at very low temperatures, within a few billionths of a degree from absolute zero. At that low temperature, the atoms have lost almost all energy. As such, they begin to clump. Since there is no more energy to transfer (as in solids or liquids), all of the atoms have exactly the same levels, like twins. The group of rubidium atoms sits in the same place, creating a "super atom".There are no longer thousands of separate atoms. They all take on the same qualities and become one blob.

Classification of Matter, Kinetic Particle Theory, Brownian Motion and Diffusion

Matter. Everyone knows what is Matter. However, does everyone know the difference between the three different stages? Why does the solid have a definite volume and shape? Why does the gas have no definite shape and volume? These questions are some of the points being discussed in this blog post about matter.
Not only that, let us think about these: Why does pollen grains move in water? Why does the food colouring spread out in a bucket of water? All these will be explained in this post.

Firstly, let us state the simple knowledge everyone should know.
Matter is anything that has mass and occupies space.
All matter can exist in 3 physical states: solid, liquid & gas, depending on the temperature and pressure of their surroundings.

What are the differences among solids, liquids and gases?

• A solid has a fixed shape and a fixed volume. It is not compressible.
• A liquid has a fixed volume but it does not have a fixed shape. It can flow and takes the shape of its container. It is not compressible.
• A gas has no shape, no surface and no fixed volume. It is highly compressible.

Let us look at the Model of the Three States of Matter:

	Solid
Diagram
Arrangement of the particles	Closely packed Regular pattern
Movement of the Particles	Cannot move freely or move from place to place Vibrate Strong attractive forces

	Liquid
Diagram
Arrangement	Particles slightly further apart Random
Movement	Particles slide past one another Free to move about . Have attractive forces between particles

	Gas
Diagram
Arrangement	Very far apart.   Randomly Arranged Takes up the space of the container
Movement	Little attraction between them  Move about randomly at a very high speed.

That is how, in detail, we classify matter. Now let us go to the complicated topics. What is the Kinetic Particle Theory?

The Kinetic Particle Theory states that matter is made of a large number of tiny particles (atoms or molecules), which are in continuous and random motion.

The Kinetic Particle Theory could be proven by Brownian Motion and Diffusion. 

Brownian Motion, is the continuous and random motion of small solid particles in fluids (liquids and gases). Brownian motion had also proved the existence of particles that cannot be observed with a normal microscope.
Brownian Motion can be observed by placing smoke particles in air. The smoke particles, when seen under the microscope, can be seen to be moving.  If heat is supplied, the motion of the smoke particles become more vigorous. Brownian Motion can also be observed by placing pollen grains in water. The pollen grains's movement is caused by the bombardment by the water molecules.
Below is an Java applet. Using small particles as the particles of a gas or liquid, and a big particles as a small solid, the Brownian Motion can be shown. Also, watch the effect when the heat has been changed.

Click to Run

Diffusion shows that particles move randomly from a region of high concentration to lower concentration.

If a bottle of perfume is opened in one corner of a room, we can smell it in another corner after a very short time as the perfume molecules have traveled from the bottle to your nose through the air. This spreading of molecules is called diffusion.

Bromine vapour can be used to show diffusion of gases. Bromine is a red brown liquid at room temperature. When it evaporates, it becomes a brown vapour. When a little bromine vapour is released into a vacuum, the brown vapour spreads through the vacuum almost at once, showing that the bromine molecules are moving at very high speed.

Diffusion of Bromine

If bromine vapour is released into a similar space full of air, the brown vapour still spreads quickly through the space but very much slower than in a vacuum. This is because the bromine molecules keep hitting the air molecules which get in the way. The air acts as a resistance.

The rate of diffusion of gases depends on the temperature and the density of the gases. The higher the temperature, the faster the diffusion, but the greater the density of the molecules, the slower the diffusion. Gases can also diffuse through walls which have pores slightly bigger than the size of the gas molecule.

Diffusion also takes place in liquids, though at a very much slower rate. An unstirred cup of coffee with milk will become uniformly coloured after many hours. In the school laboratory, diffusion of liquids can be shown using copper (II) sulfate solution and water as shown in the figure below. The two layers become uniformly mixed after a while.

Diffusion of Liquids

Measuring Equipments

This Post was not meant to be posted today. This lesson was conducted a few weeks ago...

We all know the measuring tape and the measuring rule. We, in fact, know how to use them. Here is the picture of the two.

Measuring Tape

Measuring Ruler

However, the lesson was meant to teach about the usage of the Vernier Caliper, and the Micrometer Screw Gauge.

Vernier Caliper

Micrometer Screw Gauge

Let us compare the range of measurement, and the precision (A metre rule is used instead of a measuring rule):

Instrument                         | Range of Measurement | Precision
Measuring Tape                | 0 - 5 m                         | 0.1 cm
Metre Rule                        | 0 - 1 m                        | 0.1 cm
Vernier Caliper                  | 0 - 15 cm                    | 0.01 cm
Micrometer Screw Gauge  | 0 - 2.5 cm                   | 0.001 cm (0.01 mm)

The Vernier Caliper allows the measurement of 3 different types of measurement: The External Caliper for the External Diameter; the Internal Caliper for the Internal Diameter; and the Depth Probe to measure Depth. They are represented by 1, 2, and 3 on the digram respectively.

How do you read a Vernier Caliper? This 5 minute video will teach you in detail how to use it.

This Java Applet lets you try out the vernier caliper online. (Note: Clicking on close simulation will close the webpage.)

The Micrometer Screw Gauge, on the other hand, measures in millimetres. It is usually used to measure diameter.  The method to read is shown in the two minute video below.

Though they can measure precisely, they have problems in terms of zero error. For the Micrometer Screw Gauge, zero error occurs when the zero marks on the thimble scale and the datum failed to align the thimble and anvil to meet. For the Vernier Caliper, zero error occurs when the two jaws on the vernier scale and the main scale failed to align when the jaws are completely closed.

Examples of Zero Error are as follows:

Negative Zero Error for Vernier Caliper

Positive Zero Error for Vernier Caliper

The above are zero errors for the Vernier Caliper. The 0 on the Vernier scale and Main Scale is supposed to be aligned, but it is not. The Zero Error for both are -0.08 cm and 0.08 cm each. When we are making the calculations, remember to deduct the zero error.

For the Micrometer Screw Gauge, the below photo shows the difference between no zero error, positive zero error, and negative zero error.

For this, the Positive Zero Error is 0.02mm while for the negative, it is -0.04mm.

Now, let us talk about the Ticker-Tape Timer. The information below is based on personal research, as I was only know the brief idea of this machine. This machine is better than the stopwatch, as it eliminates the problem of human reaction time. However, this timer can only be used in limited locations, and it requires some time for the data to be processed and for the actual time to be calculated.

Here is a video on the Ticker-Tape Timer:

The Ticker-Tape is attached to a machine. This machine will make the dots.

Between two consecutive dots there is a time interval of 1/50 s or 0.02 s. If there are 10 spaces on a piece of tape, the time taken for the tape to pass through will be

10 x 0.02 s = 0.20 s. 

This section of the tape is also known as a 10-dot tape. Note that the counting starts from zero.

A 10-dot Tape

Newton's The Three Laws of Motion

Newton created three laws of motion. Newton's laws of motion are three physical laws that together laid the foundation for classical mechanics. They describe the relationship between a body and the forces acting upon it, and its motion in response to said forces. The three laws, though expressed differently, can be summarised as follows:

1. Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it.
2. The relationship between an object's mass m, its acceleration a, and the applied force F is F = ma. Acceleration and force are vectors in this law the direction of the force vector is the same as the direction of the acceleration vector.
3. For every action there is an equal and opposite reaction.

The first law is famously known as the law of inertia, which explains how something cannot start or stop moving, increase or decrease its speed, or change directions without another force.

The first law of motion

An object continues to do whatever it happens to be doing unless a force is exerted upon it. If it is at rest, it continues in a state of rest. This is demonstrated when a tablecloth is whipped from under dishes on a tabletop and the dishes remain in their initial state of rest. If an object is moving, it continues to move without turning or changing its speed. This is evident in space probes that continually move in outer space. Changes in motion must be imposed against the tendency of an object to retain its state of motion. In the absence of net forces, a moving object tends to move along a straight line path indefinitely.

The Second Law of Motion

The second law says that the acceleration of an object produced by a net applied force is directly related to the magnitude of the force, the same direction as the force, and inversely related to the mass of the object. This shows that although one exerts the same amount of force on two different objects, the acceleration might be different. The acceleration on the smaller mass will be greater, for example, the effect of a 10 newton force on a baseball would be much greater than that same force acting on a truck. The difference in effect (acceleration) is entirely due to the difference in their masses.

The third laws says that forces are found in pairs. Think about the time you sit in a chair. Your body exerts a force downward and that chair needs to exert an equal force upward or the chair will collapse. The gravity is the force pulling it down, while there is an upward force that keeps you on the chair. Acting forces encounter other forces in the opposite direction.