Sunday, April 14, 2013
Sunday, March 31, 2013
Chem Blog Week 25
Over the weekend we were given the task to make an
electroscope. An electroscope is a device that is able to measure the amount of
charge an object has.
When a charged body is brought near the metal knob, both
strips acquire a like. As a result, they repel each other and spread apart to
form an inverted V. Each dangling sheet of the foil will now have a charge, the
two dangling halves of the foil will now seek to repel each other as they have
the same charge. The electroscope is then charged. If an oppositely charged
body is brought close to the knob, the charge on the strips is neutralized, and
they again hang straight down. The strips of foil hang straight down when they
are not charged. The charge will transfer to the metal foil. The degree to
which the foil flattens itself out is a measure of the amount of charge on the
foil which shows the amount of charge on the original object.
How to Make it
An electroscope model closely replicated to my final product |
After going through different prototypes of electroscopes
this is the process I found to work best. Crumple a piece of foil into a ball.
Roll the smaller piece of foil between your palms to form a long, thin rod
shape. Now connect the foil ball to the end of the rod with a thin strip of
foil. Make a hole in the middle of the jar lid with a hole punch. Be sure that
the hole is large enough for the foil rod to fit through. Slide the rod through
the hole in the lid, so the ball sits above the lid, outside the jar, when the
top is screwed on. Bend the bottom of the rod so it makes a 90-degree angle.
The angle should resemble an uppercase L. Make a narrow strip of foil and fold
it in the middle. Fold up each end of the strip to make small flaps. Hang the
folded strip of foil on the end of the rod where you formed the L shape. The
strip should hang evenly on both sides. Screw the lid tightly on the jar, with
the foil rod and flaps inside.
How it Works
The day of the
testing went great. I thought my electroscope stopped working but it was just
because the object I was using was harder to charge than something like vinyl.
There were different types made but they were all mostly based off the same
idea. I did have some trouble actually making the electroscope. My original
idea using copper wire didn’t work out because I couldn’t find any copper wire,
and even the substitute of a wire hanger for the antennae did not give any
results. I did some more research and found the best model to get the best
results. This week was fun with our project and I hope that we have another
project soon!
Sunday, March 24, 2013
Chem Blog Week 24
This week, we learned more about charges and how they work
on a molecular basis. A positive charge is one with more positive ions than
negative ions. A negative charge is the opposite. And now we know what a
neutral charge is. A neutral charge is one with an equal number of positive and
negative ions.
We were shown an experiment
including a sweater and a balloon on the SMART Board. The sweater and the
balloon initially didn't attract each other because they had neutral charges.
But, that changed when the balloon was rubbed against the wall, it became more
positive while the wall became negative. The negative ion moves. I then
wondered why the negative ions were moved rather than the positive ions. Did it
have to do with the greater electrostatic strength of positive ions than
negative ions? Or was it because the opposite charges of positive ions and
negative ions held each other in place? It seems as if though this is the case
because I think that the positive ions are stronger than the negative ions. It
seems as if though the negative ions have less strength because they have a
greater number of electrons than the positive ions. The reason I think this is
so is because I think that the less electrons there are, the less pressure is
being put on the "electro-chain" that holds the electrons in place. So
in summary the charge of positive ions is stronger than that of negative ions.
This same principle also applies to ionic compounds, which
form when ions transfer electrons to form neutral compounds. Through the
exchange of electrons one of the elements become positive while the other one
becomes negative. This is what happens when NaCl combine. The Na needed to lose
an electron while the Cl needed to gain one. So, through this "electron
exchange", the Na became positive and the Cl became negative. They then
formed an ionic compound, which means a neutral compound.
This week went pretty well. I believe I understand the concepts
we learned this week. I just need to practice with some of the equations with
the elements. We were also given the assignment to make an electroscope for Monday.
I’ve seen some videos on how to make one and it seems simple to make. But I
need to further understand how it actually works.
Sunday, March 17, 2013
Chem Blog Week 23
This week, I learned about atomic charges through a class
demonstration. When a classmate rubbed the pen on his shirt, he then held it up
to the match and the match moved–without any physical contact. I knew that the
reason was because charge but I did not know how charges work a particle level.
The first thing I learned was that a charge involves static electricity. We
found that this from the flow of Electrons. Electrons are the
smallest possible piece of an atom. This means that something is smaller than
the atom. The exchange of electrons allowed the pen to have moved the paper
clip without touching it. Because we now know that there is something smaller
than the atom we have to change the way we draw particle diagrams to represent
them at the smallest level. Particle diagrams in the past units could still be
drawn the same using dots to represent particles.
Like I said in my last blog, this week was full of new
things! I understand everything and it was easy to learn. We even had 3
experiments this week! I don’t know how next week will top it!
Sunday, March 10, 2013
Chem Blog Week 22
Next week I am guessing that since we did not get to do much
this week next week will be twice as busy. But I am okay it!
Sunday, March 3, 2013
Chem Blog Week 21
This week in chemistry we learned the connection between molar mass and density that if you know molar mass you are able to determine the density of the the element. In the case of our electrolysis experiment, hydrogen and oxygen. |
This week, my group and I did an electrolysis experiment. I was so excited because ever since we saw the process of electrolysis on the SMARTBoard I wanted to try it out for myself. We had to hook up two probes to two metals ends at the bottom of the trough. We had to fill the trough with sodium chloride water solution. But, why not water? This is the part I felt I wasn't so sure of, but I think it had to do with the fact that sodium chloride could conduct electricity in order for the hydrogen and oxygen particles to chemically split from each other.
Then we use two graduated cylinders (one for hydrogen and the other for oxygen) and put them on top of the metal ends making sure that they are still full. This was a little hard but we were able to do so in a few attempts .This reminded me of the experiment a while ago with the trough but I think this was a bit simpler because instead we had to scoop the tubes with the solution and slowly tilt them to the bottom of the trough, then tilt it again toward the metal end and cover it with the tube without going over the top of the tube. It felt like doing brain surgery with the amount of caution to flip over a test tube!
Then, after that ordeal was over with, we then cranked the machine and repeatedly turned the handle clockwise. We then kept track of the volumes for each of the tubes filled with the hydrogen and oxygen. Every time we recorded the data, there was twice as much volume of the hydrogen as there was oxygen.
We ended up finding out that compared to hydrogen oxygen is much denser even though hydrogen has twice as much volume. This adds up because we now know that the molar mass of oxygen is 16 g/mol and that hydrogen is only 1 g/mol.
This week was very fun because we did a group lab and that is one of my favorite aspects of chemistry and science in general: the experiments! With this experiment I was able to get a greater grasp of molar mass and of the fixed ratio of compounds. Feel confident with the concepts of this week hopefully I do this well next week. I am not sure what is to come next week but I trust that I won’t be disappointed with what I learn next!
Sunday, February 17, 2013
Chem Blog Week 20
We had to choose one item to compare to all the other
objects. Since the small brown nails had the least mass, we decided to compare
it to the other items, and we found the ratios of their masses to the small
brown nails. The picture above shows the data. The small brown nails had a mass
of 1.3g, the hexnuts 18.9g, the pennies 11g, the screws 10g the washers 23.6g,
the bolts 7.1g, and the panel nails 4g. The small nails to hexnuts were 1 to
14.5, small nails to panel nails were 1 to 5.46, the small nails to pennies
were 1 to 8.3, the small nails to washers were 1 to 18.15, the small nails to
screws were 1 to 7.69, and the small nails to bolts were 1 to 5.46. Therefore,
I have concluded that small nails were the smallest, and the washers have the
largest mass since the ratio between small nails and washers was the greatest.
I still felt unsure, though, on particles and how to count them. How can I represent them in a group? This question was then answered as I learned in class that for every mole, there are 6*10^23 particles. Thus, the word mole is the collective group of particles.
I still felt unsure, though, on particles and how to count them. How can I represent them in a group? This question was then answered as I learned in class that for every mole, there are 6*10^23 particles. Thus, the word mole is the collective group of particles.
We found out that like this lab, this was how scientists found the atomic masses of the elements. They compared it to hydrogen, which has the smallest atomic mass, to all the rest. Also, the overall concept I learned from this was that there can be some way of calling 6 pieces of hardware to 1 collective group (e.g. 1 dozen=12 items). 1 dozen would be the collective group. So, we came up with a collective group name for the 6 hardware pieces: the Quinn. Therefore, proportionally speaking, for every Quinn, there are 6 hardware pieces and vice versa.
With this information we are able to plug in information like
an algebraic equation and easily find an answer!
Overall this week feel okay with what I learned. I
understand the concept, however, I am having a little trouble with the
calculating of moles. I should be able to understand it with some practice.
Sunday, February 10, 2013
Chem Blog Week 19

This week, our studies were mostly based off the following experiment of chemically mixing zinc and hydrogen chloride and finding its product and its volume so I wanted to describe the process of what we did thoroughly for full understanding.
In the experiment we used a known procedure to find the volume and type of the reactant. We were told to fill a bottle all the way with water while filling the trough with water. Then, mix the zinc and the hydrogen chloride together. But, we had to seal the beaker quickly so that the gas wouldn't escape. The gas goes through an opening inside the trough by a tube connecting the two. So, to collect the product, you should fill a bottle with water and tip it over right side using a lens to prevent spilling while removing the lens afterward. (I have become a pro at this art!) Then, combine the zinc and hydrogen chloride to react. When the glass bottle once filled with water is now full with gas we used the lens again to remove the bottle.
To measure the zinc, we just put it on a measuring scale to
calculate its mass. Then, to find out the mass of hydrogen chloride, I figured
that in order to do so, we must find out the change in mass when comparing the
beaker's mass to the mass of the beaker and the hydrogen chloride in it. Then,
I subtracted the mass of the beaker with the total mass, therefore, to find the
mass of hydrogen chloride.
By finding the masses of all these variables, we figured this would be the best way to find out the total mass after the zinc and the hydrogen chloride are chemically combined together is by adding the masses of hydrogen chloride and zinc before they were combined. I assumed that since hydrogen or chlorine would escape from the system, the mass would have to decrease. With these results, we concluded that since the gas was combustible and flammable, it had both oxygen and hydrogen. But we asked the question “Where did the zinc and the chloride go?” And how did the oxygen get into the bottle? We conclude that since the air has oxygen, and since it is diatomic, it combined with hydrogen to form water. It makes sense because the bottle had condensation in it.
By finding the masses of all these variables, we figured this would be the best way to find out the total mass after the zinc and the hydrogen chloride are chemically combined together is by adding the masses of hydrogen chloride and zinc before they were combined. I assumed that since hydrogen or chlorine would escape from the system, the mass would have to decrease. With these results, we concluded that since the gas was combustible and flammable, it had both oxygen and hydrogen. But we asked the question “Where did the zinc and the chloride go?” And how did the oxygen get into the bottle? We conclude that since the air has oxygen, and since it is diatomic, it combined with hydrogen to form water. It makes sense because the bottle had condensation in it.
With this experiment it should be easy to understand the
lessons ahead and I am very excited about it!
Sunday, February 3, 2013
Chem Blog Week 18
This week, We learned about the concepts of Dalton's theory.
We later on in the week focused on the things we learned in
class on Monday and we had an assessment on Friday. I am not sure how I did,
but I know I struggled in some areas that I missed that week.
Sunday, January 27, 2013
Chem Blog Week 16/17
Monday, January 7, 2013
Chem Blog Week 15
This week I along with my group formed a
soap company with our self- made soap!
The next day they were ready to take the
soaps out of their molds and put them into their packages. We then later on had
to show our presentations to the class. Our presentation had a good layout,
great explanation, and an awesome logo edited by yours truly! We were able to answer
all of the questions given by Mr. Abud thoroughly.
I had a lot of fun with this project because
I was able to practice my team work skills. I am the type of person who likes to
work alone because I have had experiences with people not doing their part in
the assignment. But also working by myself I do not have debate with decisions
that need to be made. However, this project went fine teamwork wise but I wish
we were more prepared and connected but overall it was great!
Sunday, January 6, 2013
Chem Blog Week 14
I also learned about Heat of Vaporization and Heat of Fusion. Heat 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 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).
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 (Eph). 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 (Eth). This is what Mr. Abud was saying about water on the T-shirt if it 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 pretty noticeable to the person wearing the shirt! While the Eth did not increase the Eph did because the water turned from a liquid to a gas.
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.
Chem Blog Week 13
This week, I learned about energy transfer through the three
states of matter, and I learned about ETh and EPh.
We also did an experiment 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 . This also included us to find the original temperature
by looking at a graph of different metal colors depending on their temperature.
Then, 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. When
we found our specific heat , all the other groups compared and averaged them all out. However we
found the actual measurement of specific heat wasn’t really close to our
results!
This week was pretty easy. I understood all of the concepts
and I really enjoyed doing the experiment with the copper. I learned that when
doing an experiment like this one it is essential to pay attention to the
directions and not to rush, if not it could skew the results and someone could
be injured due to carelessness. While I still don’t have a computer these
weekly blogs still help me remember the things I learned. Hopefully I will have
it back soon, but writing them down still does the job!
Saturday, January 5, 2013
Chem Blog Week 11
In this blog I will be talking about my experience of making my thermos!
We were assigned by Mr. Abud to make a thermos that would be able to hold a Styrofoam cup and to maintain the same temperature of water (or at least as close to the original temperature) as possible.
The Design




It was fun creating the thermos and I can't wait for our next project.
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