Q: The table below lists information about the radioactive decay of three nuclides. The first two equations illustrate the initiation process, and the last two equations are examples of chain propagation. Once inside the body of a bigeye tuna or a king salmon, they become part of our food chain. Blends of PLA with polymers such as ABS have good form-stability and visual transparency, making them useful for low-end packaging applications. Because radicals are tolerant of many functional groups and solvents (including water), radical polymerizations are widely used in the chemical industry. PLLA has a crystallinity of around 37%, a glass transition temperature between 50-80 ºC and a melting temperature between 173-178 ºC. Answer the questions in the table below about this molecule with one. Inadequate control of combustion, especially for plastics containing chlorine, fluorine and bromine, constitutes a risk of emitting toxic pollutants. Thus, atactic polypropylene is useless as a solid construction material, and is employed mainly as a component of adhesives or as a soft matrix for composite materials. Derivatives of cellulose, such as cellulose acetate, have long served for the manufacture of films and fibers.
The following problems focus on concepts and facts associated with the treatment of polymer chemistry in this text. Is the speed of water molecules different in hot and cold water? Asked by GeneralKnowledgeRook94. He records his final observations in the data chemical reaction with acid changed, showing that the sample was broken down by heating. Answer the questions in the table below about this molecule is stored. The introduction of relatively large and stiff substituents (such as benzene rings) will interfere with this chain movement, thus increasing Tg (note polystyrene below). A: Hydrocarbon is defined as an organic compound which consist entirely of hydrogen(H) and carbon(C). If these rigid segments are completely removed by hydrogenation (H2 & Pt catalyst), the chains lose all constrainment, and the product is a low melting paraffin-like semisolid of little value.
The pH of the solution 6. These polymerizations often (but not always) occur with loss of a small byproduct, such as water, and generally (but not always) combine two different components in an alternating structure. NH2 1) CH2C CH 2) 'COCH CH, -CH-CH, 3) 4)…. The terms polymer and monomer were derived from the Greek roots poly (many), mono (one) and meros (part). The most common and thermodynamically favored chemical transformations of alkenes are addition reactions. Solved] Complete the table below assigning each spectrum to the correct... | Course Hero. There is little doubt, however, that biodegradable materials lead to less environmental pollution when randomly discarded after use, as is often the case. Most plastics crumble into ever-tinier fragments as they are exposed to sunlight and the elements. Students should realize that since the molecules in hot water are moving faster than in cold or room-temperature water, they should draw more motion lines. B)that is not likely to be an element.
Check all that show the elements that make up a compound. To increase the value of recovered PETE it may be depolymerized by superheated methanol into dimethyl terephthalate and ethylene glycol. Is generally limited to a few types, effective recycling is often best achieved with targeted waste streams. Their findings permitted, for the first time, the synthesis of unbranched, high molecular weight polyethylene (HDPE), laboratory synthesis of natural rubber from isoprene, and configurational control of polymers from terminal alkenes like propene (e. pure isotactic and syndiotactic polymers). Q: What is the name of the following compound OH O HO HO. LDPE is insoluble in water, but softens and swells on exposure to hydrocarbon solvents. Pure cellulose, in the form of cotton, is a soft flexible fiber, essentially unchanged by variations in temperature ranging from -70 to 80º C. Cotton absorbs water readily, but is unaffected by immersion in toluene or most other organic solvents. Q: The difference between organic and inorganic in chemistry? Check the box under each molecule in the table below that is an isomer of this molecule: - Brainly.com. The two compounds have similar chemical…. What does the speed of the mixing colors tell you about the speed of the molecules in hot and cold water? Symmetrical monomers such as ethylene and tetrafluoroethylene can join together in only one way. Monomers bearing cation stabilizing groups, such as alkyl, phenyl or vinyl can be polymerized by cationic processes. In this compound, phosphorous and oxygen act together as one charged particle, which is connected to magnesium, the other charged particle. Polyacrylates suffer thermal degradation and are therefore spun from solution in a volatile solvent.
A terpolymer of acrylonitrile, butadiene and styrene, called ABS rubber, is used for high-impact containers, pipes and gaskets. Compounds Flashcards. The polyester Dacron and the polyamide Nylon 66, shown here, are two examples of synthetic condensation polymers, also known as step-growth polymers. 1 Spectrum B 180- M 3215 8 1122 - 2984 3443 3834 2928 - 3382 1271 314 2508 150 molt between salt plates HAVENUMBERS Copyright 1992 868. Lorem ipsum dolor sit ame. For his contributions to chemistry, Staudinger received the 1953 Nobel Prize.
2 TRANSMITTANCE * TRANSHITTANCE Spectrum D Spectrum C capillary flim between salt plates liquid sample between salt plates 2928 2837 - 2983 2874 HAVENUMBERS 1853 1738 1500 1437 1580 1468 1371 puright 1992 1298 1193 Copyright 1994 1837 - $120 1833 918 1868 MOM 719 840 630. In situations that require a high level of impact strength, the toughness of PLA in its pristine state is often insufficient. The final product is amine. Answer the questions in the table below about this molecule with many. Give a short explanation why you assigned a particular molecule to this spectrum and not another. Q: A fully-mixed circular tank, 20 meter in diameter, with inflow at center and outflow along the….
Squirt 4–5 drops of yellow food coloring into another small cup for each group. Q: describes the structure formed from the FTIR results above and relates it to the lignin and…. Crystallinity occurs when linear polymer chains are structurally oriented in a uniform three-dimensional matrix. Radical polymerization gives a statistical copolymer. This property is important in applications such as gaskets and O-rings, so the development of synthetic elastomers that can function under harsh or demanding conditions remains a practical goal. 18 g of a nonionic solute is dissolved in 36.
As noted earlier, HDPE is composed of very long unbranched hydrocarbon chains. How does this match with your observations with the food coloring? 5 mg/kg PO of a drug. The molecules of cold water are moving slower and are a little closer together. A: If we compare the solubility of beryllium salts to the other Group IIA metal salts, we will notice…. A: In a nucleophile substitution reaction, the rate of the reaction depends on the nucleophilicity of…. A: Increase in BP Increase in BP Increase in BP Increase in BP Decrease in BP Increase in BP Increase…. This activity works best if there is a big difference between the temperatures of the hot and cold water. As a rule, mechanical properties such as ductility, tensile strength, and hardness rise and eventually level off with increasing chain length.
It is noteworthy that a synthetic fiber manufacturing facility occupies a much smaller area of ground than would be needed to produce an equal quantity of natural fibers, such as cotton, wool or silk. Q: HO HO, What is this molecule's chemical formula? What can we do to find out? The properties of a given polymer will vary considerably with its tacticity.
One serious problem in recycling is posed by the many additives found in plastic waste. How many unique carbon…. A: Click to see the answer. Q: How many hydrogen atoms are present in the following structure? On heating or cooling most polymers undergo thermal transitions that provide insight into their morphology. Give each student an activity sheet. Make sure to type in ALL lower cases for the names of the compounds. ) Customized catalysts that effect stereoregular polymerization of polypropylene and some other monomers have been developed, and the improved properties associated with the increased crystallinity of these products has made this an important field of investigation. Hydrocarbon polymers such as polyethylene and polypropylene may be melted and extruded into pellets for reuse. How many CHy CHz' and CH groups are in this molecule? Unfortunately, cleaning up the garbage patch is not a realistic option, and unless we change our disposal and recycling habits, it will undoubtedly get bigger.
Natural rubber is a completely amorphous polymer. A: Determine the stereochemistry of C=N as E/Z For naming the compound follow the following steps:….
Ina statement to ABC News, William C. Craigslist dogs for sale portland oregon. Powell, the director of law enforcement relations for, praised the work of the Portland police: "It's heartening to hear of owners reunited with their belongings by law enforcement armed with digital evidence we provide. It works like this: Detectives conduct sting operations by contacting suspicious sellers directly, either by sending text messages from disposable, so-called "burner phones, " or sending emails from phony email accounts. Scammers posted ads that alerted all readers that the resident was forced to leave town in a hurry, and that everything in the residence was free to the public on a first come first served basis.
Anyone with information about the incident is asked to call (503) 823-3333. Anyone who sees the vehicle is asked to call 9-1-1. The victim then moved to the passenger side of the car, opened the door and fled. She emailed the scammer and became alarmed by the response. Don't be taken in by these scams because they list the actual information listed from previous legitimate home rental posts, but if you cut the deal, you're going to lose every penny that you send them. If you want to view ads on the site you don't even have to register or sign up, but if you want to contact someone who has placed an ad or to place an ad yourself, all you need to do is sign up and it's totally free. After they gain access to personal items, they deliver some of them but steal items of value that they can sell on the black market. When he got home, there were 30 people going through his possessions and taking his belongings. In addition, the BBB lists all businesses who are members with them and if someone makes a false claim of membership you'll know that they're not safe to deal with. How to use Craigslist. Anderson cautioned against doing that. You cannot be too careful when you are dealing with strangers and when your money and your safety is involved. Is it me or is it sitting really low too? Car stolen in Northeast Portland during alleged Craigslist sale - .com. Original purchase price estimate: $430.
The incident occurred in 2012. Anderson and detective Dan Slauson, who head up the burglary taskforce, said their unit grew out of overwhelming demand. Portland police prepared to be the first buyers on the scene. Originally posted by KellyJ. For inquiries related to this message please contact our support team and provide the reference ID below. Craigslist Portland hoax scam. Type A. Craigslist for sale portland oregon travel. CCP-A 182 u. Portland for sale "sailboat". We've detected that JavaScript is not enabled in your browser. The suspects then fired two shots at the victim when he tried to follow them in his car, Simpson said. Craigslist: portland jobs, apartments, for sale, services, community... craigslist provides local classifieds and forums for jobs, housing, for sale, services, local community, and events.
It looks in pretty good condition minus the damage to the rear. Our neighbor felt the same way after they moved them. Portland craigslist free. They are separated into categories including apartments and rooms for rent, pets for adoption, services offered, personal ads, things for sale, job postings, lost and found, discussion forums and there are also other categories.
After making the deal "Nick" (Williams) disappeared with the cash and when the victim opened the box he found that there was only a book inside. You'll find that they've listed current and previous scams on the site from locals who have become victims of fraudulent activity on the site. There have been some violent crimes associated with Craigslist ads in the past but these are very few. Scammers advertised a West Linn woman's home for rent on Craigslist Portland. Oct. 26, 2011 -- Detectives at the Portland, Ore., police department's Burglary Taskforce Unit get a lot of calls like this one: "My motorcycle has been stolen; I just found it on Craigslist! There is a variety of listings on the classified ads site. The other suspect was described as an African American man, 18 to 20 years old, 5-foot-7, with a heavy build and wearing a blue sweater. The seller agreed to let him have it for $3, 500, and after he gave him the cash, the man handed him the title and made arrangements to retrieve his purchase. Craigslist cars for sale portland oregon. "Because if they don't have an outlet to sell it, they don't have a way of making money and that may discourage crime from occurring originally.
The suspect with the handgun was described as an African American man, 18 or 19 years old, 5-foot7, with a thin build and wearing dark clothing. He flagged them down to find out what was going on and they showed him the ad and refused to return the items. I am available today for questions, Saturday 6/16 and most of Sunday, then will be away for a couple of days. That call came from Portland resident Sasha Woodruff, who was certain her 2006 White Ninja motorcycle was posted for sale online. Started by kneedownnate. In the last six months alone, Portland police have helped more than 100 victims get their stuff back from Craigslist -- enough to fill a small pawn shop of their own. Please feel free to make an offer (no offer is too low). The 45-year-old victim told investigators he had agreed to meet the suspect in the parking lot of an Albertson's, located at 5850 N. E. Prescott St., to look at an iPhone the suspect advertised on Craigslist, the Portland Police Bureau said. When renters show up to move into the new home they discover that it is not really for rent and if they were mailed keys, they don't work in the locks. Prices shown are an estimate of the original purchase price only and do not reflect the current value. Five Money Scams to Watch out for on Craigslist Portland. When you deal with online ads there are no product or service guarantees. This is one of the boldest craigslist rental scams we've seen.
Looks like it's sitting right to me. They can give you insights on a business if you know the name and let you know if there have been any reports of unethical or unscrupulous business activities reported. Anyone with information was asked to call detectives at 503-823-0405. This is very much a situation where you must use your best judgement and avoid taking any unnecessary risks. Fake Best Buy Employee guilty of Craigslist Portland scam.
This is a review for craigslist in Portland, OR: "Outstanding company! Ilfospeed #4 contrast. Ilford Ilfospeed Multigrade. There are also numerous scalping scams.
Frequently Asked Questions and Answers. We own a very heavy set of living room and dining room furniture. They collect personal information on the rental application for identity theft and they make up an excuse why they can't meet with the renter in person. You must enable JavaScript to... Looks interesting: Sad to see this go, but I've got one too many projects in my life. Robbery or mugging victims kept calling the police station, saying they were finding their own stolen items being re-sold on Craigslist and they wanted help. I am a retired photo instructor and this sale is from one of my photo students. The three most common scams occurring on Craigslist Portland are home rental scams, scalping scams and hiring movers. When Sara Zachary found the deal for the 3, 800 square foot home on 1-1/4 acres for $1, 250 per month, she followed up. As of the date that this story was first reported, the suspect had not yet been apprehended. Portland police are investigating a carjacking that took place in Northeast Portland after two men met to discuss the sale of an iPhone posted on Craigslist.