Chem. Lab Methods
All work due by Friday, June 19th at 3pm. Work will not be accepted after that point.
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*background-Serotonin molecule, ball & stick form
Book work
Book work
Check your e-mail and Skyward for assignment updates. Usually Monday and Wednesdays! Weekly Chemistry will be updated Fridays.
Book Work #1 assigned 2/14, due 3/2Read Chapter 21, beginning on page 352, ending on page 368Copy and define all bold terms from chapterCopy and answer the following questions:1-Explain the difference between a physical change and a chemical change. Give examples.2-What is a chemical reaction?3-What are the parts of a chemical reaction?Check your e-mail and Skyward for assignment updates. Usually Monday and Wednesdays! Weekly Chemistry will be updated Fridays.
*cortisol molecule, causes stress, like book work
Weekly Chemical
Weekly Chemical
Copy into your notebook
Copy into your notebook
6/5: Chalk: Calcium Carbonate (classification; molecular compound, in some cases, life evidence)
6/5: Chalk: Calcium Carbonate (classification; molecular compound, in some cases, life evidence)
You draw on the sidewalk, making a hopscotch game, rainbows, and it was used to write down lectures on a chalkboard. But what is chalk? ‘Skeletons….’
You draw on the sidewalk, making a hopscotch game, rainbows, and it was used to write down lectures on a chalkboard. But what is chalk? ‘Skeletons….’
Chalk is Calcium Carbonate (CaCO3), and its origin is the ‘shells’ (coccoliths) of single celled ocean-going organisms called coccolithophores. These organisms are photosynthesis-using planktonic algae which float along the currents of the ocean at the surface, using sunlight, CO2 and H2O to make themselves. They form the basis for ocean ecosystems, transforming sun energy and inorganic chemicals in to sugars, proteins and lipids just like green plants on land.
Chalk is Calcium Carbonate (CaCO3), and its origin is the ‘shells’ (coccoliths) of single celled ocean-going organisms called coccolithophores. These organisms are photosynthesis-using planktonic algae which float along the currents of the ocean at the surface, using sunlight, CO2 and H2O to make themselves. They form the basis for ocean ecosystems, transforming sun energy and inorganic chemicals in to sugars, proteins and lipids just like green plants on land.
As they live, they collect calcium from disassociated ocean salts, combine it with CO2 from the air, and make internal shells made of CaCO3. Once they die, the shells, which are denser than the surrounding water, sink to the ocean floor. They build up over time into layered deposits, which then become chalk deposits. One of the largest deposits like this is the White Cliffs of Dover on the south coast of England.
As they live, they collect calcium from disassociated ocean salts, combine it with CO2 from the air, and make internal shells made of CaCO3. Once they die, the shells, which are denser than the surrounding water, sink to the ocean floor. They build up over time into layered deposits, which then become chalk deposits. One of the largest deposits like this is the White Cliffs of Dover on the south coast of England.
But chalk is white. So, by grinding up chalk, then mixing it with chemical powders in a liquid paste, and letting it dry, we can make a solid solution of colored chalk, that you used to make a bright, cheerful rainbow on the sidewalk, out of skeletons…
But chalk is white. So, by grinding up chalk, then mixing it with chemical powders in a liquid paste, and letting it dry, we can make a solid solution of colored chalk, that you used to make a bright, cheerful rainbow on the sidewalk, out of skeletons…
The White Cliffs of Dover, England…all skeletons…
The White Cliffs of Dover, England…all skeletons…
background: White Cliffs of Dover, SE England
5/29-Chlorine Tri-fluoride ClF3 (classification: interhalogen compound, fluorinating agent, oxidizer)Chlorine Tri-fluoride is a chemical used in rocket fuels and cleaning superconductor systems. It was investigated by the Nazis as a weapon agent in WWII, but was determined to be ‘to dangerous.’So, chlorine and fluorine are very reactive due to high EN and OSE structure. When combined into chlorine tri-fluoride, they become more reactive, even more reactive then F2 gas.Chlorine tri-fluoride is a chemical so corrosive that it cannot be stored in glass. It is such a strong oxidizing agent that it will burn things that will not ignite with oxygen.Asbestos will ignite when exposed to it. Ashes of things already burned in oxygen will catch fire when exposed to chorine tri-fluoride as it reacts with the carbon powder left over from some combustions. Due to the instability of the bonds, it does not need any extra energy to ignite. In the 1950’s, 900 kilograms (2,000 lb.) of chlorine tri-fluoride spilled on the concrete floor of a storage facility, dissolving 1/3 meter (about 1 ft.) of concrete and 1 meter (3 ft.) of gravel under it.The only (relatively) safe way to store or transport this chemical is in a metal (carbon steel, completely cleaned of any residue) container which has already been treated with fluorine. This creates a fluoride barrier with which the chlorine tri-fluoride cannot react. It can be stored in a solid quartz container with no flaws.When chlorine tri-fluoride meets water, the chemical reacts explosively. It generates heat and hydrofluoric acid.5/22-Calcium Oxalate, CaC2O4 (classification: calcium salt of oxalate, urine waste product) Oxalates are compounds found in various foods and typically bind to Calcium during digestion to form Calcium Oxalate, which is removed from the body in feces and urine. It is typically soluble in urine as long as the urine is neutral in pH (acid=below 7pH, basic=above 7pH). In most mammals, this leads to normal, safe removal of CaC2O4 through urine as urine is typically between 6.5 and 7.5pH. But, the solubility of CaC2O4 decreases if the pH of the urine drops below 6.5, especially in dogs. This causes CaC2O4 to crystalize in the bladder in between episodes of urination. These crystals collect together with other compounds in the bladder to being to make ‘stones’ of mostly CaC2O4. These can sometime pass through the urinary tract if small enough, and only cause moderate pain. If the stones remain without being passed, they can grow in size, becoming large enough to not be able to be removed without surgery.Of note, other causes of ‘stone’ formation include low water intake combined with a high oxalate diet. Again, the solubility level of the CaC2O4 is exceeded, and crystals form. Temperature decrease doesn’t cause stone formation, as the body temperature of mammals is steady, comparatively, in a living animal, so temperature is not a factor in oxalate solubility in urine. The source of most oxalates in diet is mostly from plants, like spinach and potatoes. 5/15 Helium He (classification: Element, Noble gas)It makes your voice squeaky and your birthday balloons float away due to different density than normal ‘air,’ (.1786g/L compared to 1.429g/L for O2). Earth’s gravity is not strong enough to hold significant amounts in the atmosphere, so when it leaves your balloon, most of it escapes into space. So, where do we find it on earth?The answer lies in radioactive decay. The decay of heavy radioactive isotopes like Uranium 238 when it decays to Thorium 234, releasing an Alpha particle (2p2n) which collects in underground deposits of natural gas and interacts with Beta particles from other radioactive decays to become helium atoms. At one point, it was thought that supplies of helium might run out, but new discoveries of natural gas locations with helium have shown that is not a current concern.The most common use of helium in industry is in super-cooling superconductor magnets, insulation in arc welding and making silicon crystals for the computer industry. Filling the Goodyear blimp and other lighter than air applications is a very minor use of the gas.While rare on Earth, it is the second most common element in universe, being a major component in stars. The gas giant planets also have helium in fairly large 5/8: Jewel wasp venom, various compounds (classification: weaponized organic compound mixture, nerve toxin)I see your murder wasps, and raise ya with…The Jewel Wasp (Ampulex compressa) is a solitary wasp classified as an entomophagous parasite, meaning it parasitizes insects, in particular, cockroaches. It has a sting, like any wasp, which it uses to attack the cockroach. Here is where it gets weird. The roach is stung twice. Once at the thorax (waist) to immobilize the legs temporarily, then a second sting is applied at the base of the head, right at the control centers for the roach brain. After being stung the second time, the roach does not die, it grooms itself for approximately 30 minutes, and all flight instincts seem to disappear. The poison also slows the roach’s metabolism. During this grooming time, the wasp goes off and digs a burrow. The wasp returns, grasps the roach by an antenna, and ‘leads’ it to the burrow. The wasp leads the roach down the burrow into a room it has hollowed out, where it lays one egg on the roach’s abdomen. It then leaves and fills the burrow entrance. The roach now rests quietly as the egg hatches, the larva burrows into the roach’s abdomen and, without killing it, proceeds to eat the internal organs in an order which will keep the roach alive until it is done growing, and forms a pupa inside the roach’s body. The new wasp then hatches, leaves the burrow and goes about its life. Throughout this process, the roach is alive, and aware. It seems to feel itself being eaten, and the pain thereof, it just doesn’t have the motivation to leave…all due to the neurotoxin poison effects on the brain…Ahh, chemistry!