This 8th Grade Science class will be embarking into the world of educational blogging. Students will be writing about what we are covering in our class and providing information for those interested. Please join us in this experience.
On Friday 28th, after showing our colored periodic tables to ms.D, we were told that we are going do a lab about exothermic and endothermic reactions. We had to read about them for that day, so everybody already knew what they were. For you people that had the shame of missing our class, or just aren't part of it (which is also a shame), here is a definition of both:
- Exothermic Reaction: A change in which energy (or NRG) is released.
- Endothermic Reaction: A change in which energy is taken in.
So, the purpose question was "How do measured temperatures show the difference between an exothermic and endothermic reaction?"
In the actual lab, we mixed Yeast with Hydrogen Peroxide, and Baking Soda with Vinegar. Yeast and Baking Soda being the Solutes, and Hydrogen Peroxide and Vinegar being the Solvents. After consulting it with ms.D, we decided that the independent variable of the lab was temperature, and that the dependent variable of the lab were the endothermic and exothermic reactions. The result of the first experiment was that Yeast and Hydrogen Peroxide became instantly very bubbly and hot, and stunk like rotten bread.
The second experiment was a bit slower, as the chemical reaction took longer to occur. The result was lots of bubbles and the container becoming cold.
All of the experiments went without any injury and everyone left with good data. The whole lab is in our Chemistry Packet, so check it out!
If you still don't understand the difference between endothermic and exothermic reactions, here is a link showing some simple examples of them.
Thank you for reading my scribe post. I hope you enjoyed it and that it was helpful.
The next scribe is... well, I can't find the list of available scribes, so I'll have to ask ms.D.
Today, May 27th, our class was about reviewing things from Chemistry Unit for our final exam. First off all, Ms. D asked us to go Dr. Heslips office. There we took some pictures and later visited Dr. Haddons balcony to take a picture with Mr. Houlis. After taking some lovely images, Ms. D and us returned to the classroom. There we started discussing exercises that were on the chemistry quiz we took Tuesday, May 25th. Here is the list of the exercises including the answers and the notes we took with Ms. D.
Protons vs. Electrons
Proton is a stable particle with positive charge equal to the negative charge of an electron. It is also found in nucleus and it is made from quarks.
Electron is an elementary particle with negative charge. It is also spinning around the nucleus. It can also be found in a lightning.
Matter vs. NRG
Matter is anything that takes up space or anything that has mass.
NRG is not matter, it is an ability to do work or cause change.
*Mass vs. Weight
Mass is the amount of matter inside an object. Uses kg or g as units. It also stays the same.
Weight is the amount of force put on the object by gravity. Uses newtons as units. It also changes itself depending on the position. (Ex. On the moon, on the poles.)
Solute vs. Solvent
Solute (dissolute) is a mixture that is added to the solvent, where the solvent dissolves it. The process is called a chemical change. (Chemical change – a change in matter that produces one or more new substances.)
Solvent (dissolvent) is a substance that is mixed with the solute.
(Ex. Cedevita: solute = powder, solvent = water)
Homogeneous vs. Heterogeneous
Homogeneous mixture is a mixture where you can’t see the different parts. (Ex. Alcohol.)
Heterogeneous mixture is a mixture where you can see the different parts because everything is grouped up. (Ex. Sperm.)
*Capacity vs. *Volume
Capacity is the amount of matter an object can contain.
Volume is the amount of 3-dimensional space occupied by an object.
*SI is the metric system that measures them. Here is the list of some other chemistry-related vocabulary words.
Shape– a 3-dimensional geometric shape.
States of Matter –a distinct state of matter in a system; matter that is identical in chemical composition and physical state and separated from other material by the phase boundary.
Molecular Motion –the movement (average) of particles in a state of matter.
Molecular Proximity – distance of particles in a state of matter.
To see a Table about the States of Matter, please click on the link below:
Last thing Ms. D said is the relation to today’s world; if someone would solve the Filament state of matter, and make it be together and stay for more than one second, that person would create a whole new type of energy, more efficient one. So, that means that no more oil or gas needs to be spent. After the long reviewing session, Ms. D showed us the assignments for homework, located on Moodle.
Due Friday, May 28th:
1. The 7th Blog Comment. Remember, you must have three 8th grade comments, three 7th grade comments and two 6th grade comments. 2. Color in the TWO Periodic Tables in your packet - be sure to read the directions for what you need to do for each. Follow the link below:
In class Friday we went over the liquids and solids observed in a lab on Thursday. As a class we decided which substance was compound which was an element and which substance was a mixture. After everyone went up and wrote substance under where they thought it belonged we all went through to check each-others answers. This is what we ended up with:
In the table below the numbers next to the letters underneath "symbols/formlas" are meant to be down lower and smaller-like in this image- REMINDER: Quiz tuesday: -over 3 parts in your book you read as homework -your chart in the packet -and the 2 sets of notes
Elements:
pure substance (simplest)
can't be divided
no "+"'s in formula
and has only one chemical symbol
Compounds:
pure substance
2 or more elements combined chemically
has a ratio (always the same)
ONE chemical formula
Mixtures:
2 or more elements involved
NOT CHEMICALLY combined
2 or more chemical formulas
formulas have "+"'s
TYPES OF MIXTURES:
Homogeneous- uniform mixture, same throughout Ex.cedvita, mineral water, salt water
Heterogeneous-not uniformed mixture, not same throughout (Looks like a salad. You can tell where the tomato is, where the lettuce is, where the cucumber is; it all stands out) Ex.soil
Solution is a homogeneous mixture. 2 parts:
-Solute(what you have less of): part that dissolves
-Solvent(what you have more of, and usually a liquid): dissolving part
Examples- In salt water: solute-salt solvent-water
In cedvita: solute-orange powder solvent-water
In mineral water- solute-CO2(gas) solvent-H2O (liquid)
Stated by Ms. D, "96% of the time H2O is the solvent"
ONE LETTER ELEMENTS: O H N C
TWO LETTER ELEMENTS: He Cu Au Fe Li Cr Ge
THREE LETTER ELEMENTS: Une Uun Uuu And these are all, man-made solids, and last less than a second usually.
¬We also figured out how to read the substances formulas' using math.
In the formula above there are 4 hydrogens, because you multiply H x 3 and you get 3 hydrogens. Then add the H at the beginning. and you get a total of 4.
There are also 2 carbons and 2 oxygens used to create the substance.
In case you want to look up more formulas, this is a cool site I used:
Today in class we had Mr. Tim as our teacher because Ms. D went on a field trip with the 7th graders.Mr. Tim discussed elements, compounds, and mixtures to us.
An element: a substance which cannot be broken down into other substances by ordinary chemicals. Each element is represent by a symbol. Example: oxygen = O , gold = Au, helium= He
A compound: two or more elements can be combined to form compounds. Compounds are very different from the elements from which they are formed. Example:NaCl, made from sodium, a dangerous and explosive element, and chlorine, a poisonous gas.
A mixture: made from two or more substances, elements, compounds, or both in definite proportions, and these proportions are not always the same. Example: soil, cake, milk
Homogeneous mixture: the substances in a homogeneous mixture are so evenly mixed that you can't see the different parts. Example: cake batter, petrol, plastic spoon
Heterogeneous mixture: in a heterogeneous mixture you can see the different parts. Example: salad, gravel, car
After discussing those topics, we reviewed temperature, weight, mass, volume, and density. We gave a definition, units, and the equipment used for each property.
Temperature: - a measure of the average NRG of motion of the particles of a substance
- Celsius and Kelvin
- thermometer
Weight: - a measure of the force of gravity on an object.
- Newtons, kilograms
- force scale, spring scale
Mass: - a measure of how much matter is in an object.
- kilograms
- TBB
Volume: - the amount of space that matter occupies. -centimeters cubed -ruler, graduated cylinder Density: - the measurement of how much mass of a substance is contained in a given volume -TBB, ruler
Finally we got to our rotation lab on matter. In this lab we had to smell and examine 12 different substances and write down their symbol/formula, their physical properties, decide if the substance was a solid, liquid or gas and decide if it was an element, compound or mixture.
Here are some substances that were examined: .
Copper- Cu, solid, element
Hydrogen peroxide- H2O2 , liquid, compound
Rubbing Alcohol-C3H8O, Liquid, compound
The homework from today is to complete "States of Matter-pg 42-47" and by reading those pages fill out States of Matter Note Taking Section in our Chemistry Packet.
Also don't forget another blog comment is due tomorrow (Friday).
On May 14, 2010 we had a short Friday class, first everyone got their constellations project back graded. We watched the Myth Busters season 4 – this time the myth they tested was Mentos & Diet Coke.
Here is a link to the video that inspired the myth:
On Thursday in class we learned about the history of the big bang, and its theory. It was first proposed in 1927 by a priest named Georges Lemaitre.
Big Bang Order:
1) We started of as NOTHING!
2) The first big bang is thought to have been equivalent to dropping a 2.2 kg's bag of sugar.
3) What we call the "Real Big Bang'' was an inflation or an expansion of the universe that interrupted the standard linear expansion shortly after the first big bang.
4) Particle Soup- HUGE amount of matter formed which gets cooler and gets a larger volume (plus, - , 0 , Q , N) In other words:
(protons, electrons, neutrons, quarks, neutrino)
5) The first elements after this were;
1) Hydrogen- (first most abundant element/ first created element)
2) Helium- (second most abundant element/ second created element)
3) Lithium- (third most abundant element/ third created element)
What happens next?
Scientists are still debating on which one of the three will happen next.
Some say the universe will have a continual expansion
Some say it will have a "big crunch" and it will all crunch together
Others say that eventually everything is going to stop
At the end of class we got a Chemistry Unit Note Taking Guide and a Chemistry Packet.
In the Chemistry Unit Note Taking Guide we have to do the thirteen questions about Describing Matter which is on pg. 6-15 in the textbook.
And bring Chemistry Packet to every class from now on!!
Last Friday, we spent class reviewing eachother's constellation fact sheets. Each student recieved 3 people for whom he or she was to read their sheets and grade them. Because that class was short and unchanging, I am also blogging for today's science class on May 11.
Today at the beginning of class we had a quick discussion about Branimir; the astrophycsicist that came to our class and talked to us last week. We wrote him some of our comments and criticisms on his lecture, which included the following: Criticisms: Lack of media Shorten his bullets on his powerpoint Speak louder and clearer Interact with the students more Simplify some vocab
Compliments: Showed enthusiasm and true knowledge of the subject Gorgeous pictures Interesting at most parts
Branimir has never taught to students our age; and I think he deserves an extra arm of applause for having the courage to do so now. In about three days, he becomes a doctor of astrophysics.
From the discussion, Ms.D continued to show us the Star Notes Powerpoint we had started to watch in one of our previous classes. Our final exam will include most of this information, which is why I will include a summary of the most important facts below.
Stars: -Blue stars are the partiers. They are hot, big, young and die fast. -White stars are middle everything. Middle aged, middle sized and middle brightness. -Red stars are old, colder and dying.
A globular cluster is a glob of stars
Galaxies: Galaxies are large systems of stars in dust (interstellar matter) There are several million galaxies with several trillion stars in each one. There are three main types of galaxy: -Spiral -Elliptical -Irregular
Spiral galaxies: Our galaxy is a spiral galaxy Young populations Have lots of interstellar matter Has arms and a a black hole in the middle
Elliptical galaxies: -Old populations -Very little interstellar matter
Irregular galaxy: -No shape, distorted due to gravity from neighbouring galaxies
We know other galaxies exist because of the use of math, and pictures taken using radio waves
Additionally, we learned what a Hertzbrung Russel graph is. It is a graph that explains how stars age.
Next, we were taught how a star dies. There are basically three different ways of stellar death, and how they go is based on their mass.
-If the star is the mass of our sun: Red Dwarf: Running out of fuel Red Giant: Out of fuel Nova-Explodes White dwarf-Hot, small star, dead when it runs out of energy
No worries, our sun won't die for another 4 million years, and we'll most likely die out by then anyways.
-If the star is 4x the mass of our Sun Same steps as Sun Past White Dwarf Electrons+protons combine = neutrons= neutron star! The neutron star then becomes stronger than nucleur forces inside of an atom
-If the star is 10x the mass of our sun -Same steps as previous deaths -Past neutron star -Collapses past nucleur forces -Forms a gravity well-cosmic vacuum cleaner -Which then turns into a black hole
In the middle of our discussion, we also talked about atoms and molecules , and learned that zombies are actually just reanimated atoms.
At the end of class we began a discussion on the Big Bang, but ran out of time. For the next class the volleyball girls will not be here to take notes so I hope the next blogger does a supreme job of summing up the class.
We have no homework for Thursday. Also the following link is something spiffy I found that stimulates all of the astronomical events we discussed in class. http://www.youtube.com/watch?v=hoLvOvGW3Tk
Additionally, something I personally found intriguing was that when we look into space, we look into the past since things are so many light years away. For example, if there is a galaxy one billion light years away, we won't know its dead until a billion years from now.
On Tuesday a guy came in and told us about the universe and wormholes and physical theory and stuff like that. He works as a theoretical Physicist at the university here in Zagreb. The difference between a Theoretical Physicist and an Experimental Physicist is that a Theoretical Physicist makes up mathematics, and an Experimental Physicist tests those mathematics. The man who came in is clearly a Sci-Fi enthusiast, and yes, Star Trek does teach you stuff.
This man went briefly into supernovas. Apparently, there are 5 types of supernovae, each more difficult to explain than the last.
That there is a cool looking supernova, so I decided to throw it in.
Then the guy went on to talk about wormholes and parallel universes. Wormholes are supposed to be like a shortcut in space, its like going across the Pacific in a Honda to get to China, thus far impossible. Not to mention the negative energy and stuff. Apparently, energy can go backwards according to this man (which is supposed to be a violation of physics because all energy needs to move forward or be non-existent) but that is what is theorized to be in the "Throat" of a wormhole. Also, there is no going through wormholes without going backward or forward in time, so it's relatively impractical to be something that is used on a regular basis.
Today, I wasn't there but we had to work on a Constellations project. It is due tomorrow. You can find instructions and Rubrics on Moodle.
On Friday, April 30, 2010, our science teacher, Mrs. DiPietro gave us a presentation about stars. She told us that stars differ in size, mass, color, temperature and brightness. The colors that stars have are blue, yellow, and red, and that their life cycle is as long as sun's, which is 9 billion years. If the star is blue, then it tells that the star is young a very hot, about 35,000 degrees Celcius. Blue stars can also die out sooner than other stars. If the star is yellow, then it is middle-age star. If the star is red, it is cold, around 3,000 degrees Celcius, and it is about to die.
Our teacher also explained us about the sizes of stars (see pictures at the left). First, she told us about Supergiant stars. Their size is 1000 times the diameter of the Sun. These star giants include Rigel, Betelgeuse, and Antares. Then our teacher told us about giant stars. They are 10 to 100 times as large as a sun, and these include Sirius, the brightest star in our sky. We learned that the stars come from Nebulae, and sometimes from EGGs (Evaporating Gaseous Globules)
We also learned Binary stars are stars that stay together because of gravity between them, and that there are 88 accepted constellations in our sky.
Today in science class, we had a shortened period becuase of a Croatian field trip. However when we got back, Ms. D continued to show us a powerpoint of the two comets Halley and Hale-Bopp. The powerpoit explained their revolution and when they will reach Earth again. We also were reminded about the five parts of a comet.
The five parts of a comet are:
1.Nucleus-middle part which is composed of gasses, dirt, and ice
2.Dust tail- composes of dust
3. Ion tail- different color, heating up and exciting gasses
4. Coma- the gasses around the nucleus. They cause the shine
5. Hydrogen cloud- the gasses that are released and left behind
Now a little bit about the two comets Hale-Bopp and Halley.
Comet Halley:
-It is the most famous comet in history
-It proved Edmund Halley's math was correct becuase the comet came back to Earth
-It originates from the Oort Cloud
-It is now currently located in the Kuiper Belt
-The revolution is 76 Earth years (it last came in 1986 and it will come back again in 2061)
-It is the same age as the Sun (4.5 billion years old)
Comet Hale-Bopp:
-It was discovered in July 23, 1995
-Two people discovered it independently Alan Hale and Thomas Bopp
-It is 4.5 billion years old
-The diameter of the nucleus is 40-80 kilometers
-Its revolution around the Sun takes 2,392 Earth years
After talking about the comets, we continued our forum and concluded it. We talked about Mars, Jupiter, and Neptune. Not having much time left, we quickly reviewed the names of the celestial bodies and their symbols'. We were told that there is a review session on Wednesday during lunch if you want to come.
REMEMBER, TOMMOROW WE HAVE A CELESTIAL BODIES OPEN NOTE TEST! REMEMBER TO COME PREPARED! The test will be timed so organize your stuff well.
During the Science period of Friday, April 23 2010, we additionally explored the activities being held later on this year. In the first minutes of class, Ms. D mentioned that our scheduled "Celestial Body Test" had once again been postponed as the Croatian classes are taking a trip to a theatre. Despite the fact that we are not having our test on Tuesday, Ms. D still highly recommended you prepare yourself (the chart) over the weekend. She took this further by saying that we CANNOT share our notes with anyone in the class as they will be taken away from both you and the person you shared them with. Prior to that, Ms. D made it clear to take blogger more seriously, look at what you are posting, chose your videos wisely, and make sure your commenting is appropriate, as she will be showing this Blog to others. Keep in mind, you need 3 Eighth grade posts, 3 Seventh grade posts, and 2 Sixth grade posts for Blogger. If experiencing trouble commenting on the 6th and 7th grade blogs, scroll to the bottom of the page where the verification button is as this will allow an access to commenting. Astronomy then ends on May the 7th, and we will be moving forward into Chemistry. As discussed, we will only be having Chemistry, and very little Astronomy in our Science Final.
As class prolonged, Cornelia
and Abigail gave there Celestial body presentations, discussing them amongst each class table. Cornelia's given Celestial body focused on Comets. Comets are leftovers from the creation of the Solar system around 4.5 billion
years ago. They are made of ice and are coated with dark organic matter. She also described how Comets are predicted to have shared water and other organic compounds with the Solar System and Earth's early life.
The 5 Parts of a Comet
1.) Nucleus
2.) Coma
3.) Hydrogen Cloud
4.) Dust Tail
5.) Ion Tail
Cornelia's favorite Comet was Hale Bopp. Like other Comets, it has a revolution of 2,392 Earth days and comes from the Oort Cloud. Comets are given the name of icy snowballs or mud balls and when they are in contact with the Sun (around 15 AU's close), they dissolve into gas.
Gas determines the color of the Comet
Red light - Hydrogen
Blue light- Carbon Dioxide
Yellow Light - Oxygen
As Cornelia concluded, Abigail began to tell us about Mars, her Celestial Body. The Planet Mars is particularly smaller compared to other Planets. It is a red color, due to its soil composed of rust. The planet has large dust and wind storms including diminutive tornadoes. Mars has been researched for any sign life. Yet all that has been found was frozen water beneath its surface. This planet holds onto 2 moons. One of them, Phobos, is predicted to smash into Mars since it is swinging closely around its atmosphere. Once this occurs, gravitational forces will shatter the moon to particles. Moreover, Mars consists of 3 rovers or robotic machines developed for taking better pictures and accurate research.
Afterward, the class continued the open forum by adding additional information to both Mars and Comets along with reviewing Questions and Answers brought up by the class.
Dates
-Thursday April 29th is our Open Note Celestial Body Test and remember to come prepared. Ms.D will also hold a review session for this test on Wednesday, April 28th
-Extra Credit is due Friday May 14th. Take a picture with Saturn, Neptune, Uranus, or Pluto for 3 extra bonus points and email the picture to dani.dipietro@aisz.hr or ddipeitro.aisz@gmail.com
-Tuesday April 27th - 5th APOD is due. This one can come from any date from 2000-2010
-April 30th - 3rd Blog comment to 7th or 8th grade Blogs
Here is an Awesome Video on Mars and a helpful one on Comets, also focusing on other Celestial Bodies.
Today, in science class, April 22nd, 2010, we continued our forum discussion in connection with the planet packet. However, we first focused on a very important event which is happening today, the 40th anniversary of Earth day. Earth day was started in the US in 1970 but the UN celebrates international Earth Day on March 20th/ 21st. On this special day they also ring a peace bell.
In connection with Earth Day, we will also be planting plants tomorrow and take them home as a way to give back to the environment.
In our discussion about Earth day we brought up some important things such as one major problem at the moment: global warming. It is referred to as the extremes in climate which have drastically changed in the past years. The causes of global warming are being discussed and there are many theories; but, Ms. D pointed out that since carbon emissions have increased in the past years there have been extreme changes in weather patterns. If this process continues we may even end up resembling Venus; The hottest planet which melts metal on its surface, which would not be a pleasant thought!
Lastly, we watched videos and a slideshow in connection with Earth Day. The links to the videos are just below:
During class, Ms. D also gave us corn starch Styrofoam which indeed is very edible. (:
As we moved on to the Forum we mainly focused on Exosolar planets and Daniel explained his topic during class. Extra notes you missed if you were not in class today or just didn’t pay attention:
- The smallest exosolar planet they have found is Jupiter size
- The 4 spacecrafts with the sole mission of leaving this solar system are called Voyager 1, Voyager 2, Pioneer 10, and Pioneer 11. These all went in different directions in our solar system!
- Further explanation of 3 ways to find Exosolar planets:
1) Radical Velocity Method
-It is Earth based
-They find rays from the Parent star (Star which Exosolar planets orbits around) and measure the wavelength. If this wave length is abnormal or weird they suspect that they have found an Exosolar planet.
-The top of a wavelength is called a crest and the bottom a trough.
2) Astrometry Method
-Space based
- Looks at the wobbling of a star
- Star wobbles because gravity affects it
3) Transit method
- Most surefire method
- Both Earth and solar system based
- Watches the changing brightness of a star
We also had a very cute visitor from 3rd grade named Alice. She came to observe our astronomy forum class for the last 20 minutes. The class introduced themselves and their planets to Alice while we continued the forum.
Homework & Upcoming events
April23rd : second blogger comment for the 4th quarter is due!
April 27th at 8 AM: The fifth APOD for this unit any date from 2000-2010 may be used! Also, next week is the last APOD that will be due for science this year!
April 28th : Celestial Body test study session at lunch
April 29th : open note Celestial Body Test
April 30th : third blogger comment due
May 4th or 7th: A friend of Mrs. Sprljan may come in to talk to us about astromomy. He specializes in wormholes and Black holes.
May 11th : Chemistry unit starts
May 14th : Extra credit due. Each picture next to a planet is worth 2 points. The planets which count as extra credit are Saturn, Uranus, Neptune and Pluto. Email these pictures to dani.dipietro@aisz.hr or ddipietro.aisz@gmail.com for extra credit. Good luck!
Here are the maps for the extra credit assignment: http://www.phy.hr/~mpozek/planeti/
Hebrew: Ohevet otchem kulam (Love ya guys) and good luck (:
Here is a link to the video that inspired the myth:
