Monday, January 2, 2017

Essential Questions
How was radioactivity discovereand studied?
- In 1896, the French physicist Antoine Henri Becquerel accidentally found that a uranium-rich mineral called pitchblende emitted invisible, penetrating rays that could darken a photographic plate enclosed in an opaque envelope.

- In 1898, Marie Curie began her doctoral study of Becquerel's rays. She and her husband, Pierre, soon discovered two new radioactive elements, which she named polonium, after her native land of Poland, and radium, because it radiates. These two new elements filled holes in the periodic table and displayed much higher levels of radioactivity than uranium. Over four years, working under poor conditions and spending their own funds, the Curies processed more than a ton of uranium ore to isolate a mere gram of radium salt.
In 1898, Marie Curie began her doctoral study of Becquerel's rays. She and her husband, Pierre, soon discovered two new radioactive elements, which she named polonium, after her native land of Poland, and radium, because it radiates. These two new elements filled holes in the periodic table and displayed much higher levels of radioactivity than uranium. Over four years, working under poor conditions and spending their own funds, the Curies processed more than a ton of uranium ore to isolate a mere gram of radium salt.

Source: Boundless. “Discovery of Radioactivity.” Boundless Chemistry Boundless, 26 May. 2016. Retrieved 02 Jan. 2017 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/radioactivity-134/discovery-of-radioactivity-534-3691/
In 1898, Marie Curie began her doctoral study of Becquerel's rays. She and her husband, Pierre, soon discovered two new radioactive elements, which she named polonium, after her native land of Poland, and radium, because it radiates. These two new elements filled holes in the periodic table and displayed much higher levels of radioactivity than uranium. Over four years, working under poor conditions and spending their own funds, the Curies processed more than a ton of uranium ore to isolate a mere gram of radium salt.

Source: Boundless. “Discovery of Radioactivity.” Boundless Chemistry Boundless, 26 May. 2016. Retrieved 02 Jan. 2017 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/radioactivity-134/discovery-of-radioactivity-534-3691/
In 1896, the French physicist Antoine Henri Becquerel accidentally found that a uranium-rich mineral called pitchblende emitted invisible, penetrating rays that could darken a photographic plate enclosed in an opaque envelope.

Source: Boundless. “Discovery of Radioactivity.” Boundless Chemistry Boundless, 26 May. 2016. Retrieved 02 Jan. 2017 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/radioactivity-134/discovery-of-radioactivity-534-3691/In 1896, the French physicist Antoine Henri Becquerel accidentally found that a uranium-rich mineral called pitchblende emitted invisible, penetrating rays that could darken a photographic plate enclosed in an opaque envelope.
In 1896, the French physicist Antoine Henri Becquerel accidentally found that a uranium-rich mineral called pitchblende emitted invisible, penetrating rays that could darken a photographic plate enclosed in an opaque envelope. While working on phosphorescent materials, he happened to place the pitchblende on black paper that he had used to cover a piece of film.

Source: Boundless. “Discovery of Radioactivity.” Boundless Chemistry Boundless, 26 May. 2016. Retrieved 02 Jan. 2017 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/radioactivity-134/discovery-of-radioactivity-534-3691/
In 1896, the French physicist Antoine Henri Becquerel accidentally found that a uranium-rich mineral called pitchblende emitted invisible, penetrating rays that could darken a photographic plate enclosed in an opaque envelope. While working on phosphorescent materials, he happened to place the pitchblende on black paper that he had used to cover a piece of film.

Source: Boundless. “Discovery of Radioactivity.” Boundless Chemistry Boundless, 26 May. 2016. Retrieved 02 Jan. 2017 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/radioactivity-134/discovery-of-radioactivity-534-3691/
In 1896, the French physicist Antoine Henri Becquerel accidentally found that a uranium-rich mineral called pitchblende emitted invisible, penetrating rays that could darken a photographic plate enclosed in an opaque envelope. While working on phosphorescent materials, he happened to place the pitchblende on black paper that he had used to cover a piece of film. When he looked more carefully, he noticed that the film had lots of patches on it, and that this did not happen when other elements were placed on the paper. He eventually concluded that some rays must be coming out of the uranium crystals to produce this effect.

Source: Boundless. “Discovery of Radioactivity.” Boundless Chemistry Boundless, 26 May. 2016. Retrieved 02 Jan. 2017 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/radioactivity-134/discovery-of-radioactivity-534-3691/
In 1896, the French physicist Antoine Henri Becquerel accidentally found that a uranium-rich mineral called pitchblende emitted invisible, penetrating rays that could darken a photographic plate enclosed in an opaque envelope. While working on phosphorescent materials, he happened to place the pitchblende on black paper that he had used to cover a piece of film. When he looked more carefully, he noticed that the film had lots of patches on it, and that this did not happen when other elements were placed on the paper. He eventually concluded that some rays must be coming out of the uranium crystals to produce this effect.

Source: Boundless. “Discovery of Radioactivity.” Boundless Chemistry Boundless, 26 May. 2016. Retrieved 02 Jan. 2017 from https://www.boundless.com/chemistry/textbooks/boundless-chemistry-textbook/nuclear-chemistry-19/radioactivity-134/discovery-of-radioactivity-534-3691/
What are the key properties of alphabetaand gamma radiations?

- Alpha particles (α) are helium nuclei emitted by nuclei of high atomic number.  For a given isotope they are monoenergetic (they all have the same energy).

The product nucleus has an atomic number that is two less, and a mass number that is four less, than that of the original nucleus.  Alpha particles are ejected with high energy.  They efficiently ionize atoms in their path.  They do not travel far but produce intense ionization within a short path.  They travel at 5% to 7% of the speed of light.



 - Beta particles (β) are high speed electrons.  β-emission is equivalent to the conversion of a neutron to a proton.

The product nucleus has an atomic number that is one more than that of the original nucleus.  The mass number remains the same.  With their high speed, up to 90% of the speed of light, single negative charge, and extremely small size and mass, the high energy β particles pass through matter much more easily than do α particles.  The β particles are not monoenergetic and a spectrum of energies is obtained, with a characteristic maximum energy that corresponds to the actual energy transition in the nucleus.

Gamma rays are a form of high energy electromagnetic radiation and travel at the speed of light. Because of their high energies and their ability to penetrate deeply into matter, they can do considerable biological damage. They have neither mass nor charge. γ-emission often accompanies α- or β-emissions, since these forms of radioactive decay frequently leave the product nucleus in an excited state. This unstable state can go to a lower energy state with the emission of electromagnetic radiation, which, for the nucleus, is in the γ-ray region of the spectrum.
Review Vocabulary
nucleus: the extremely small,positively chargeddense center of an atom that contains positively charged protonsneutral neutronsand is surrounded by empty space through which one omore negatively charged electrons move.
New Vocabulary
radioisotope - an atom that has excess nuclear energy, making it unstable
X-ray - a form of electromagnetic radiation ranging from 0.01 to 10 nanometers in wavelength
penetrating power - ability of radioactivity to pass through materials

Saturday, September 3, 2016

Should we make recycling mandatory?

Yes, we should make recycling mandatory, but not everyone has to recycle. Given that everyone always sorts the waste, we only need a few people to help all of us recycle.

1. Recycling drastically reduces waste

A lot of garbage can be recycled for using them again, and the results are pretty much the same. Sorting the items again and recycling make the procedure much easier and it is more efficient to use as many times as we can. If we don't recycle, it will take as long as ten thousands of years to degrading the products. For example, plastics are one of the best inventions that will take only a few days to recycle, but take thousands of years to decompose itself. Therefore, we should recycle those to reduce waste.

2. Recycling conserves the materials

All of the items in our daily life are made of natural resources, and they are limited resources. If we don't recycle, we will let their supposedly usable items gone extremely hard to reuse them. Most of the products will be consumed by degradation, but we can resurrect them to reuse those materials again. For example, wood will degrade faster than plastics, but wood takes longer time to create again. We can recycle used paper to make another paper to lessen the deforestation for wood. If you don't recycle, it is like burying money in the ground and never use them again.

3. Recycling can make you new products

 Not only you can reduce waste products and conserve materials, you can also get new products from the litters as well. Some products can be changed to something different based on your own creativity to design products. For example, you can recycle plastics to make a 3d-printed prostheses to disabled people. It is the most useful and easiest practice to know how to recycle.

Friday, September 2, 2016

Should genetic engineering be allowed?

Genetic engineering should be supported in order to develop today's technology. This studies have been improving our lives without even noticing.

1. Genetic engineering improves the source of food we eat.

Genetic engineering is the result of agriculture and animal farming. They all start from selective breeding, where the good traits are selected for mass reproduction. In this way, the best product will be served to us. For example, bananas used to yield way less fruit than now, oranges used to give little juice while using less amount of water, and even more. Therefore, genetic engineering can make us better lives.

2. Genetic engineering discovers something new.

Although some would claim that contamination of new organisms is unacceptable, it is actually a good thing to try discovering new things. Those are considered an evolution of organisms just like how organisms are evolved for millions and millions of years. Some organisms may accidentally or intentionally cause an alien species contamination for a long time ago, those are what made us today. It is not considered a bad thing to discover something new.

3. Genetic engineering can cure defective genes.

It seems like editing a gene is like solving a ten-million-by-ten-million Sudoku, but we can potentially use genetic engineering to cure a lot of defective genes. For example, Cystic Fibrosis and Huntington's disease are the most serious issue that are caused by just a single missing nucleotide. Genetic engineering can actually solve this problem and reduce the number of people who have these diseases.

Wednesday, August 17, 2016

Fruit Batteries

Batteries have 3 parts, cathode, anode and the electrolytes. In this lab we are trying to find the voltage of a fruit, by setting up cathode and anode on the juicy fruit as an electrode.





Equipment: fruits (orange, lime) crocodile clips, copper, iron, magnesium, voltmeter, ammeter, scissors

Procedure:
1. Roll the fruits to make the inside more juicy.
2. Plug the 2 different electrodes into the fruit by not having them touch each other.
3. Plug the voltmeter to measure the voltage inside the juice.

Results
Fruits: Orange
Anode: Zn, Cathode: Cu -> Voltage = 0.2V
Anode: Zn, Cathode: Fe -> Voltage = 0.1V
Anode: Fe, Cathode: Cu -> Voltage = 0.05V

Fruits: Lime
Anode: Zn, Cathode: Cu -> Voltage = 0.3V
Anode: Zn, Cathode: Fe -> Voltage = 0.1V
Anode: Fe, Cathode: Cu -> Voltage = 0.15V

Conclusion
- Orange gives off more voltage than lime.
- Zn gives off electrons easier than Fe and Cu from the standard potential cell order.

Tuesday, July 26, 2016

Terrarium Lab: WHY ARE MY FISH DYING?

1.       Why do they die?  What's your hypothesis?
- They die because they don't have enough oxygen, the temperature is different, or the pH of water changes.
2.       What are our variables?
- amount of sunlight, temperature, animal, pH
3.       Which container increased in temperature the most?
4.       What were the initial temperatures?  Are there any increases
- 29 28.5 28 29 28 28.5 27.5 27 (degrees Celsius)
-  There is an increase of temperature on all bottles.

Tuesday, July 12, 2016

Electrolysis of NaCl solution

This experiment shows the electrolysis of an aqueous solution of table salt (NaCl)

Equipment: NaCl, universal indicator, battery, alligator clips tray, paper.


Procedure:
1. Prepare an aqueous solution of 2 M NaCl (58.5 g in 500 ml)
2. Add universal indicator in the solution. The solution changes the color into green.
3. Attach an alligator clip to the battery on both sides. The electrolysis should progress.
4. As electrolysis progresses, color changes will begin to occur.
5. Place a neodymium magnet in the middle and observe the flow of electron.

Results:
- The anode generates gas, and the cathode has a black substance on it.
- As the magnet is placed, the flow of electron travels in a circular motion, making the color as a circle. The flow changes direction if the pole of magnet is switched.

Discussion:
1. Why is the universal indicator green when you first add it? Water has a pH of 7 so it changes the universal indicator as green.
2. Why can we use the pencils to run a charge. Pencil can conduct an electricity as graphite.
3. What is the color at the cathode? White gas
4. What is the color at the anode? Black precipitate
5. What happens when you place the niobium magnet? Why? The flow travels in a circular motion
6. What is the equation for the electrolysis of water? Without e and volts? 2 H2O -> 2 H2 + O2
7. Why can we dump the solution down the drain? The NaCl solution and universal indicator not poisonous.

Tuesday, June 28, 2016

Titration lab

- used to determine the concentration of an unknown solution
- the known concentration is used for titration in a burette
- a pH indicator is used for determining the equivalence point, where the concentration of H+ and OH- are the same.

Equipment


Procedure
1. Rinse the burette inside thoroughly with the solution it will contain.
2. Fill the burette at the scale zero using a graduated cylinder.
3. Record the starting volume, then start the titration. Slowly turn on the stopcock and let the solution flow. As the color starts to change to fuschia pink, swirl the solution until it is clear. If the solution cannot stop getting clear, the titration is completed.
4. When you complete the titration, record the volume of solution used for titration.