## Tuesday, May 17, 2011

### Final Exam Review: #20 and #31

20) A white powder is analyzed and found to contain 43.64% phosphorous and 56.36% oxygen by mass. The compound has a molar mass of 283.88 g/mol. What are the compound's empirical and molecular formulas?

$43.64 g P*\frac{1 mol P}{31.0 g P}=1.41molesP$
$56.36gO*\frac{1 mol O}{16.0 g O}=3.52 moles O$
$P_{1.41}O_{3.52}=P_{1}O_{2.5}=P_{2}O_{5}=empirical formula$
$2(31.0)+5(16.0)=142.0$
$\frac{142.0}{283.88}=\frac{1}{2}$
$empirical formula*2=molecular formula=P_{4}O_{10}$

31) A topic not covered by the final exam review is how a nuclear reactor works:
A nuclear reactor is basically a system of recycled water. The water is heated and is turned into steam which travels down a steam line to spin the blades of a turbine. The turbine then turns the shaft of a huge generator, where electricity is produced. The steam then cools down back into water and the cycle repeats. Control rods prevent the reactor from overheating and when they and the fuel rods are spent they are placed in a cooling tank called a "swimming pool".

## Thursday, April 7, 2011

### Chernobyl

Kira
April 7, 2011
Honor Bound
B6
The Accident at Chernobyl

Nuclear power plants produce electricity when the reactors split atoms of an element. The heat that the nuclear reaction emits creates steam. The steam then powers the reactor’s generator, which in turn creates electricity. The water in the reactor serves as a coolant that prevents the plant and reactor from overheating. The generator ignites the spark while the turbines turn it. Meanwhile, radioactive material heats water into the system in the reactor’s core.
Parts of modern-day Belarus, Russia, and Ukraine were greatly affected by the radiation. Five million people were in contaminated areas and unluckily, there are many ways in which a human being may be affected by the toxic radiation. First of all, the steam can scald someone. Also, radioactive fallout can cause thyroid cancer, mainly found in children. Surprisingly, just simply the fear of radiation can cause severe cases of stress. Another effect of the Chernobyl radiation is the contamination of locally grown food. To prevent inhalation of the contamination, local food is often thrown out in a fallout area, which decreases the amount of nutrients citizens have each day. Also, during the time of the Chernobyl tragedy, many women decided to have abortions due to the fear of having radiated contaminated fetuses. Symptoms of radiation poisoning may include nausea, vomiting, a brief appearance of no illness, headache, and fever. Late symptoms may include dizziness, weakness, fatigue, hair loss, low blood pressure, and the coughing up of blood. At the time of the incident, more than 100,000 people were evacuated from surrounding areas and some of the land today is still contaminated.
Fukushima, today however, in Japan has had more explosions in their nuclear reactors than Chernobyl did almost twenty-five years ago. Chernobyl’s RMBK reactors were Russian models (reaktor bolshoy moshchnosty kanalny) with the coolant of water, similar to Japan’s Light Water Reactors. However, Chernobyl it has been learned from the Chernobyl incident in places such as Japan to not use graphite as a moderator. Also unlike Chernobyl, Japan’s incident was cause by a natural disaster, a tsunami, whereas Chernobyl’s tragedy was a result of employee error and unstable reactor models. Also, the workers at the power plants at Fukushima did as instructed in case of an earthquake emergency, so they are not at fault. In Japan, the power that kept the cooling system running was shut off by the tsunami; therefore, the reactor overheated and caused explosion. Whereas Chernobyl was a badly executed safety test, Japan was simply a freak accident.

Works Cited:
“Chernobyl.” PBS.org. N.p., n.d. Web. 6 Apr. 2011. <http://www.pbs.org/‌wgbh/‌pages/‌frontline/‌shows/‌reaction/‌readings/‌chernobyl.html>.
“Chernobyl Accident.” World Nuclear Association. N.p., n.d. Web. 4 Apr. 2011. <http://www.world-nuclear.org/‌info/‌chernobyl/‌inf07.html>.
“Chernobyl Health Effects: Best Available Data.” Atomic Insights. N.p., n.d. Web. 6 Apr. 2011. <http://atomicinsights.com/‌1996/‌04/‌chernobyl-health-effects-best-available-data.html>.
“How Is Japan’s Nuclear Disaster Different?” National Geographic. N.p., n.d. Web. 7 Apr. 2011. <http://news.nationalgeographic.com/‌news/‌energy/‌2011/‌03/‌1103165-japan-nuclear-chernobyl-three-mile-island/>.
“How Nuclear Power Works.” How Stuff Works. N.p., n.d. Web. 7 Apr. 2011. <http://www.howstuffworks.com/‌nuclear-power.htm>.
“Preface: The Chernobyl Accident.” International Chernobyl Radiological Portal of the ICRIN Project. N.p., n.d. Web. 4 Apr. 2011. <http://chernobyl.info/‌Default.aspx?tabid=294>.
“Pressurized Water Reactor Diagram.” TVA. N.p., n.d. Web. 7 Apr. 2011. <http://www.tva.gov/‌power/‌wbndiag.htm>. Picture