Dec. 12-16

Q/m=amount of energy per
unit of mass

This week, I reviewed over energy. In between particles, attractions and chemical bonds involve electrostatic interactions. This is what holds the particles together. Like magnets sticking onto the refrigerator because the magnetic poles attract to the metal on the refrigerator, particles work the same way.

I also realized that the attraction between particles depends on the physical changes of a substances. These states of water are very different not only because of their physical states but because of the attraction of their particles. Solid has stronger attraction between particles because the particles in a solid have the least amount of energy so the particles are closer together--like relatives who live a few blocks in contrast to miles away. The lesser the distance, the greater the contact and the visits. That is what happens in a solid. The particles have strong attractions and move the least because there isn't enough energy to change the arrangement of particles.

LOL diagram of water evaporating

However, in a gas, the particles are the farthest apart. In this case, the relatives live miles away from you, which means less contact during the year. In a gas, the particles barely bump into each because they are farthest apart. The particles in a gas, thus, have the most amount of energy because it takes a higher amount of energy to separate the particles and make them move faster.

When physical states of substances change, this is because the attractions between the particles must be overcome in a solid to change to a liquid or gas. But, let's keep this in mind. Just because the arrangement of particles changes, it doesn't mean that the motion of particles has changed. They could still move at the same rate. For example, a dozen cars drives straight to the store each at 25 miles per hour. But, when six cars change direction and drive to the mall at the same speed, it only changes the arrangement of traffic.

Heat of Fusion and Heat
of Vaporization

This is what occurred when water at a temperature of 100ºC was not boiling. Even though the arrangement of particles became less structured, not enough energy, though, could cause the substance to change state. As a result, the liquid still remained a liquid with different arrangement of particles.

The same goes without saying for the motion of particles. Just because it changes, it doesn't mean that the arrangement of particles has. The cars on the highway could still be going the same destination and if they accelerated from 65 miles per hour to 70 miles per hour, the cars would still be in the same order. So, in particles, if the motion of particles has changed and not the motion, then this means that they had enough energy to make them move faster but not enough energy for the substance to change state. Thus, particle attraction was not completely overcome since not enough energy was in the th account.

State changes in Heat of Fusion and
Heat of Vaporization and
particle motion

For instance, this is what happened when the water on the T-shirt evaporated. The state of the water changed from liquid to gas, but the temperature of the water couldn't have change because if it were at the boiling point (100ºC), it would be scalding! So, what then caused the water to evaporate? Energy did. Enough energy in the ph account was used to change the motion of the particles and accelerate them. However, there was not enough energy to change the arrangement of particles. Thus, the preconceived notion that water had to evaporate at 100ºC is not entirely accurate.

Therefore, a solid has the most orderly arrangement of particles and the lowest amount of energy as well as motion of particles. The liquid has the second most fluid arrangement of particles, meaning they move freely about but not as rapidly as gas particles. Thus, liquid is more structured than a gas and has less energy. Gas has the most amount of energy with the particles being the farthest apart with the least attraction. Thus, the distance between the particles and the attraction between them has an inverse relationship much like volume and density.

This week, I learned about Heat of Vaporization and Heat of Fusion. Heat of Vaporization (enthalphy of vaporization) is the amount of energy that is required to convert a unit mass of a liquid into the vapor without a change in temperature. Heat of Vaporization occurs in state changes of liquid to gas and vice versa: (Vaporization) or (Condensation). Heat of Fusion (enthalphy of fushion) is the amount of energy that is required to convert a unit mass of a solid into the liquid without a change in temperature. Heat of Fusion occurs in state changes of solid to liquid and vice versa: (Melting) or (Freezing).

Dec. 5-9

This week, I learned about energy transfer through the three states of matter, and I learned about ETh and EPh energy.

Eph is the phase energy that is transferred when an object changes its state. So, if a solid changed to a liquid, there would be more phase energy since this made the particles move more freely. The particles are not rigidly structured like a solid. Rather, the density of the liquid is less than that of the solid because of the arrangement of the particles and the amount of space they are taking up. When a substance changes state from liquid to gas, the particles of gas are arranged even more freely and are spread out the most.

However, the problem is this: If solid changed to liquid without temperature, then why did it change state? The reason is because the amount of energy required to arrange the particles increases since more energy is required in a liquid to break bonds in solid in order to make the particles move freely about in contrast to the rigid and structured solid. In a solid, the particles move slower because they are in a crystalline structure, and it requires less energy to keep the particles closer together.

Eth is the thermal energy that is transferred when an object's temperature changes. The motion of the particles changes. As more energy is applied to a substance, its particles move faster and at greater distances and more freely. The greater the thermal energy, the more likely a substance is going to change state. However, enough energy has to be applied to a substance in order for it to actually change state. To change the motion and speed of the particles, the amount of energy changes the attraction between the particles. If the particles have a weak attraction, then the particles will move faster, and if they have a strong attraction, then they will move slower. Thus, in a liquid, the particles of a liquid have a weak attraction since they are not closely together. In contrast, a solid has the strongest attraction between the particles since they are the closest together. A gas has the weakest attraction because the particles are the farthest together.

What determines the attraction between the particles, though, is the term "field," which is the area around an object where non-contacting force can be exerted. Phase energy is stored in fields to arrange whereas thermal energy is stored in fields to change the motion of the particles.

I also participated in an experiment where I had to find the specific heat of copper. This week, my group and I had to come up with a procedure before we started. First, we had to measure the mass of the copper, then the water's mass, then, the temperature change of copper after putting it in water and the temperature change of water. Then, algebraically, I set the specific heat formula of water to the specific heat formula of copper equal to each other to figure out the specific heat (c) with E=mcΔT formula for both. Since the volume of water was 150 ml, and the density of water is 1g/ml, its mass was 150 g, the temperature change was 12.5ºC, and the specific heat is 4.18J/gºC. With the copper, the mass was 39.5 g, and its temperature change was around 480ºC. 
So, my mathematical procedure was this:

1. (39.5)(c)(Δ480)=(150)(4.18)(Δ12.5)
2. 17,520c=7,837.3
3. c=0.41J/gºC

The question remained: Was it the correct specific heat for copper? The algebraic process of showing how I found the specific heat was correct, but it may or may not have been correct. (this was mere speculation before I found out its specific heat of copper is 0.39J/gºC). So, I then thought of the possible sources of error. I considered that massed could have calculated incorrectly. Or, the temperature change could have been calculated incorrectly since the only way to determine this is to observe the color it changes to, which may have been mislabeled, contributing to incorrect temperature. It is also possible that I measured the water's temperature incorrectly.

I thought that since these were possible sources of error, I figured that if the mass of the copper were, then the specific heat of copper would be less than it should be or more than it should be. If the temperature change of the copper was miscalculated, then specific heat would be less than it should be or more than it should be. If the mass of water were miscalculated, then specific heat would be less than it should be or less than it should be. If the temperature change was miscalculated, of water were miscalculated, then specific heat would be less than it should be or more than it should be.

Nov. 26-30

The center topic discussed this week was on specific heat. Previously, we learned that heat is the energy, whereas energy is just energy, and the amount of it dictates what the temperature is.

But, specific heat is a new term this week. So, what is specific heat? First, to differentiate between heat and specific heat, specific heat is not the transfer of energy. Heat is.

My process of learning what specific heat went like this. I was asked what the meaning of the formula for specific heat is. But, I didn't exactly know that it was the formula for it, but I intuitively assumed, partially erroneous though, that it had to do with the amount of heat associated with the amount of joules (Q) affecting the change in temperature (showed by Δ temperature in ºC) in a substance with a certain mass (m).

Although I had the general concept down, I erred with the word heat. Heat doesn't directly affect temperature. Thus, I learned that heat itself is just an entity of the transferring of energy. Although it affects the temperature to some degree, it doesn't necessarily affect it. What affects it the most is the energy itself. Thus, I coined that heat is the means to the energy, the energy the cause, and the temperature the ends.

In class, I learned that specific heat is the amount of change that is required to change the temperature of    1 gram by 1ºC. I also learned that specific heat=energy/(mass x Δ temperature), and specific heat=Joules (J)/(grams x ºC).

This week, I reviewed the degree of hotness (temperature) and quantity of hotness (heat). The question I had to answer was which temperature increased the temperature of the water more? The 50ºC 25g water or the 100ªC 5g water?

This graph shows the Triple Point of water.
The triple point is the point where a substance
is in between all three states of matter.

To figure out which one had more heat, I considered which one had a higher temperature, since the amount of energy and heat were directly related. Since the 5g water at 100ºC had a higher temperature than the other water, I though that this would have the greater quantity of hotness. However, I also  thought that to understand how the different temperatures affected the temperature change of water, the masses of each of the two waters seemed to play a factor in temperature change. Since the 25g water had greater mass, I thought that it had greater energy since there were more 5x more particles in the water than in the 5g water. Although the temperature in 5g water is hotter, it would take more energy for the particles to move in 25g since there is a greater mass. Thus, the greater the mass, the greater the temperature change is.

I found out that when I learned what specific heat is, I was correct in my reasoning. With specific heat, I realized that the greater the mass, the greater the amount of energy used to increase temperature change with a larger mass. Thus, I then thought of a hypothetical situation where I had to measure the specific heat of each of the two waters using the same temperatures and masses. I then made up a certain amount of joules using x for both. Since both their specific heats were 4.18 J/gºC, I was correct in assuming that the value of energy had to be found out for both waters.

So, with water 1– 4.18 x 25g x 50ºC, and then with water 2– 4.18 x 100ºC x 5g. As I made my calculations, I was correct in hypothesizing that water 1 had greater amount of energy. Thus, it has more mass as well as the amount of particles. I also noticed that water 1 had greater volume than water 2 since the amount of particles in water 1 took up more space with a greater mass than water 2.

I also learned this week about graphing the change in states of matter: from solid to liquid, solid to gas, etc. I then learned that two factors affected the changed states of matter: pressure (atm) and temperature (ºC). So, I then considered, that if there were enough pressure, water could change from solid to gas skipping liquid state, and CO2 from solid to liquid skipping gas state. I observed that the closer it gets to the boiling point (100ºC), the more likely an ice cube is going to evaporate into water and skip the liquid state change. Although I theorized that substances can skip states of matter, I now understand that pressure and temperature dictate this, so it has furthered my understanding of their direct relationship. Otherwise, it wouldn't make sense if CO2 skipped liquid state because the pressure was greater and the temperature was less, and vice versa.