Effects of MTV Essay -- essays research papers

The negative effects of MTV on our society and culture What do you think about when you hear the word MTV? Carson Daily counting down the top ten on Total Request Live? Bam Margera doing insane stunts on his new show BAM? How about The Wild Boys chasing alligators and poisonous snakes? MTV has revolutionized and affected the whole world through its negative influence on society and culture. MTV has in many ways corrupted our youths and American culture with shows such as Jackass, with their dangerous acts of stupid ness, and Marilyn Manson encouraging suicide and murder. One can say MTV is promoting violence. MTV has grown to be a major component in the music industry and its change from video based programming in the past to the television series focused on today has had some major ef...

Gravimetric Determination of Phosphorus in Fertilizer Samples Essay

I. Abstract The purpose of this experiment is to determinethe Phophorus content of fertilizer samples using Gravimetric Analysis. It involves dissolution of the fertilizer sample, precipitation and heating and cooling of the sample. Pooled standard deviations of the two data sets for % Pwet, %Pdry, %P2O5 wet and %P2O5 dry were 5.1448, 5.1472, 11.8436 and 11.8504 respectvely. During the experiment a data rejection for %P and %P2O5 was concluded at approximately 20% and 47%. Determination of the Phosphorus content in fertilizer is vital in quality assurance and in the choosing of a fertilizer grade important for agriculture. II. Introduction Plants require essential nutrients such as Nitrogen, Phosphorus, Potassium or Sulfur to grow. However, most soils lack these macronutrients thus a decrease in food production. In connection with this, the use of fertilizers containing these macronutrients has been part of the agricultural tradition. Fertilizers have in its labels a set of numbers, known as the fertilizer grade that always appear in the form N-P-K, indicates the proportions of essential nutrients present (ie 10-10-10 which means 10% Nitrogen, 10% Phosphate in the form of P2O5, 10% Potassium in the form of K2O). Different organizations worldwide like Association of American Plant Food Control Officials (AAPFCO) in the United States, conduct different tests to assess the accuracy and consistency of the nutrient content with regards to that of the product label and also to ensure quality assurance as part of consumer rights. Analysis of fertilizer can be conducted using Gravimetric Analysis. In Gravimetric Analysis, the product with known composition is resulted from the conversion of the analyte to a soluble precipitate that can be easily filtered and is free from impurities by subjecting it to heat. This product of known composition will then be weighed and the percentage of the analyte in the sample can be determined. In this experiment, the analyte, Phosphorus in the fertilizer will be precipitated as Magnesium Ammonium Phosphate Hexahydrate, MgNH4PO4 ( 6H2O: 5H2O + HPO42- + NH4+ + Mg2+ + OH- ( MgNH4PO4 ( 6H2O (s) (1) The purpose of this experiment is to determine the percentage of Phosphorus (P) and Diphosphorus (P2O5) in the fertilizer sample by the means of Gravimetric Analysis. III. Data and Results In this experiment, the wet (as received) and dry weights of the fertilizer sample, obtained from the previous experiment of moisture determination of the same fertilizer sample were used. Weights were divided into two data sets, Data Set 1 having four (4) trials and Data Set 2 having three (3) trials. The dried sample from the previous experiment from which moisture was determined, was dissolved and is converted into a sparingly soluble precipitate, MgNH4PO4 ( 6H2O which is then filtered and weighed. The filter paper used was weighed to easily determine the weight of the precipitate. The precipitate was then dried and weighed. IV. Discussion This experiment aims to determine the percentage of P and P2O5 in fertilizer sample using Gravimetry. The fertilizer sample from the previous experiment of Moisture Determination was utilized in this experiment. The dried fertilizer sample was dissolved with 40 mL distilled water and was then filtered to obtain a clear filtrate. In Gravimetry, it is important to use a precipitating agent that if not specific, should be selective and would give out a precipitate containing the analyte. This precipitating agent should also give out a precipitate that is easily filtered and washed from impurities, unreactive with the elements present in the atmosphere, of low solubility to lessen the loss of analyte during filtration and washing, and with known composition after drying or heating. In this case, 45 mL of 10% MgSO4 ( 7H2O was added to the filtrate, with 150 mL 2M NH3 as the precipitating agent to obtain the desired precipitate MgNH4PO4 ( 6H2O which contains the analyte P. See Equation 1. While other precipitating agent like NH4Cl can be used, NH3 was used otherwise to ensure that the desired precipitate would be form. The presence of Cl- ions will more likely to attract Mg2+ thus producing MgCl2 precipitates, which do not contain the analyte in this experiment which is P. It should be noted that NH3 is added slowly with continuous stirring to the solution to ensure the growth of the precipitate, resulting to a precipitate that is easier to filter and be freed of impurities. This technique is related to the von Weirman’s ratio wherein the particle size of a precipitate is inversely proportional to the value of Relative Superaturation given by: Relative Supersaturation = [pic] Where: Q= concentration of reactants before precipitation S= solubility of the precipitate Precipitates are either formed by nucleation, or by particle growth. In nucleation, particles join together to form a large mass, usually a result of supersaturation in solutions. It consists of huge amount of precipitate, however, is composed of small particles that are hard to filter. In this experiment, what is desired is particle growth that yields a precipitate of large size but of smaller number. This is possible by further precipitation wherein particles adhere to the surface of initially nucleated particles. The supersaturation state of the solution is eased during constant stirring upon addition of the precipitating agent, thus promoting particle growth rather nucleation. With respect to the von Weirman’s ratio, the higher the value of the ratio, the higher the possibility of getting smaller particles, thereby promoting nucleation, contrary to a lower value of the ratio which promotes particle growth that will yield larger precipitates that is important in this experi ment. After the addition of the precipitating agent with constant stirring, the mixture was allowed to stand at room temperature for 15 mins. It is important to let the mixture stand, without any agitation or external forces acting on it to let digestion to occur. Digestion is necessary to allow reprecipitation, wherein particles will adhere to the initially small precipitates, and to expel water molecules thus lessening the surface area available for adsorption which causes impurities to obtain larger particles with greater purity and easier filterability. After 15 mins, the mixture was filtered using the preweighed filter paper. The filter paper that was preweighed was kept in the dessicator until further use to keep the moisture from adhering to the filter paper. Preweighing the filter paper was helpful for easy determination of the weigth of the precipitate. During filtration, precipitate was washed with distilled water in small portions of 5mL twice. For each washing, the distilled water was poured into the beaker where precipitation occured to accumulate the remaining precipitates that adhered to the sides of the beaker. After washing with distilled water, two 10mL portions of 95% ethanol were used for second washing. The use of 95% ethanol, becaue of its volatility thus will dry the precipitate faster, will ensure that no more water is trapped in the pores between the precipitates, minimal solubility loss and particles of small size will not loosen up and pass through the pores of the filter paper. Smaller portions of the wash liquid were used to ensure that the precipitate will still be intact and nosignificant loss in the amount of the precipitate due to the overflowing of washes liquid. The filter paper containing the precipitate was then heated inside the oven set a t 110˚C for 1 hour and was cooled in a dessicator for 15 min. After this, the weight of the precipitate was determined by subtracting the value of the preweighed filter paper with the weight of the filter paper including the precipitate. Even though Gravimetry is considered as one of the efficient and less expensive ways of determining a fertilizer component, this technique is still not fool proof and errors due to determinate and indeterminate factors may lead to an erroneous result. One of these errors is the fast addition of the precipitating agent and low impact of agitation that leads to the production of larger amount of small particles that may pass through the filter paper thus having lesser amount of precipitate, and a lower value for the P or P2O5 content in the sample. On the other hand, since while the mixture stands in room temperature without any coverings, contaminants like dust particles may be included in the mixture, contributing weight to the precipitate, giving a higher yield. This high yield will give a P or P2O5 content of the sample higher than its actual value. It can be observed from Table 3 that the range of % P and % P2O5 lies between approximately 6% to 13% and 15% to 30% respectively with 20% and 47% suspicious values since it is almost double of the values in range. By performing the Q test, the values were confirmed to be accpetable with regards to the actual value and values in the population, or rejected. Table 4.1 and 4.2 shows the values that were rejected and accepted for each data set. Notice that the 20% and 47% for % P and % P2O5 respectively, both belonging to Data Set 1 were rejected with 95% confidence level, meaning that the Qexp exceeded the value of the Qtabulated. Of all the trials in both Data Set 1 and 2, the group with values similar to that of the rejected values were the ones who obtained the greatest amount of precipitate. See Table 2. This rejection or errounous error in the data can be attributed to the determinate and indeterminate errors in the experiment. One more error that could be the reason for this rejection is the personal error in terms of the reading of the analytical balance. Also, because of this rejection in data, aside from the fact that Data Set 2 has lower number of population, Data Set 2 parameters for Measure of Precision are closer to each other, with the dried samples having greater values than that of the wet sample. Iti s because dried sample are purer than that of the wet sample containing still moisture and other interfering agent to getting the actual % P and % P2O5. V. Summary and Conclusions In this experiment, it was determined that the fertilizer sample has % P range of 6% to 13% with % P2O5 from 15% to 30%. However, the usual types of fertilizers with phosphates contain a minimum of 42.5 % water soluble phosphate and 46% total phosphate by weight, as in the case of Triple Superphosphate or 85 % water soluble and 20% available in Superphosphate. It should be noted that the theoretical values will vary depending on the type of fertilizer used in the experiment. Despite the data rejection that occurred, overall, it can be said that the experiment is a success since the objectives of the experiment such as performing gravimetric analysis in the determination of phosphorus content and to know the principle in separation by precipitation were achieved. Yet, it is recommended that there would be a specific manner of putting the precipitating agent, like addition dropwise or certain amounts per second or stirring so as to ensure the proper formation of crystals needed by the experiment. It should also be observed that upon digestion, or letting the mixture stand without agitation, the mixture should be covered to avoid impurities present in the atmosphere. VI. References Chapter 3: Gravimetry. California State University, Dominguez Hills. < http://www.csudh.edu/oliver/che230/textbook/ch03.htm> Accessed 17 January 2013. Fischer, R.B. and Peters, D.G. Quantitative Chemical Analysis 3rd ed. 1968; pp42-43;49 Food and Agriculture Organization of the United Nations. AGP – Fertilizer Specifications. http://www.fao.org/agriculture/crops/core-themes/theme/spi/plantnutrition/fertspecs/en/. Accessed 04 January 2013. Rehm, G. et al. Understanding Phosphorus Fertilizers: Phophorus in the Agricultural Environment. University of Minnesota: Extension. 2010. < http://www.extension.umn.edu/distribution/cropsystems/dc6288.html> Accessed 17 January 2013. Skoog, D. et al. Fundamentals of Analytical Chemistry 6th ed. Saunder College Publishing. 1992; pp72-80

How to Cut Down on Your Cars Greenhouse Gases

Greenhouse gases, responsible for global climate change, are emitted in large part from the combustion of fossil fuels like oil, coal, and natural gas. Most of the emissions from fossil fuels come from power plants, but second ranked is transportation. In addition to carbon dioxide, motor vehicles release particulate pollution, carbon monoxide, nitrogen oxides, hydrocarbons, and volatile organic compounds. Maybe you have already adjusted many aspects of your lifestyle to reduce your carbon footprint, including installing LED lights, turning down the thermostat, and eating less meat. However, in your driveway sits glaring evidence of one source of greenhouse gas that you could not get rid of: your car. For many of us, especially in rural areas, bicycling or walking to school and to work may not be an option, and public transportation may simply not be available. Do not fret; there are still actions you can take to lower the pollution and greenhouse gas emissions you produce when driving. Fuel Economy vs. Emissions We generally assume a vehicle with better fuel economy will also release fewer harmful emissions, including greenhouse gases. The correlation generally holds true, with a few caveats. Decades-old vehicles were built under much more relaxed emissions regulations and can be prodigious pollution producers despite a relatively modest thirst for fuel. Similarly, you may be getting 80 miles per gallon on that old two-stroke scooter, but that smoke will contain much more harmful pollutants, much of it from partially burned gasoline. And then there are the cars with emission control systems releasing illegal amounts of pollution, like those finger-pointed during the infamous Volkswagen small diesel engine scandal. The obvious place to start to reduce emissions, of course, is by choosing a modern vehicle with the best possible fuel economy. Models can be compared using a handy web tool put together by the U.S. Department of Energy (DOE). Be realistic about your needs: how many times a year will you really need a pick-up truck, sport-utility vehicle, or minivan? Performance is another fuel economy killer, but if you really want a sportier car, favor a four-cylinder model with a turbocharger instead of a larger six or eight (or twelve!) cylinder car. The turbo kicks in on demand, with the more frugal four cylinders doing the work the rest of the time. Manual vs. Automatic Not so long ago manual transmissions provided better fuel economy than automatic transmissions. It was a good excuse for those who love to row their own gears but modern automatic transmissions, which now have 5, 6, and even more gears, provide better mileage. Continuous Variable Transmissions (CVT) are even better at maintaining the engine’s revolutions at the right speed, beating even the most skilled stick-shift enthusiasts. Older Car, Newer Car Older cars were designed and constructed in the context of emission regulations that were much less restrictive than they are today. Much improvement has been made in the 1960s, with the development of the catalytic converter and fuel injection, but it wasn’t until the soaring gas prices in the 1970s that real fuel efficiency gains were made. Amendments to the Clean Air Act gradually improved car emissions starting in 1990, with important gains made in 2004 and 2010. Generally, a more recent car will have better technology to reduce emissions including electronic direct fuel injection, smarter electronic control units, lower drag coefficient, and improved transmissions. Maintenance You probably heard this one before: simply keeping your tires inflated to the proper level will save you in fuel costs. Under-inflated tires will cost you as much as 3% in fuel costs, according to the DOE. Maintaining proper pressure will also improve your stopping distance, reduce risks of skidding, rollovers, and blowouts. Check for the appropriate pressure on a sticker located in the jam of the driver-side door; do not refer to the pressure value printed on the tire sidewall. Replace your engine air filter at the interval specified in your owner’s manual, or more frequently if you drive in especially dusty conditions. The dirtier your air filter is, the more fuel you will use. Do not ignore lit check engine lights, even when you feel like the car is operating normally. Often the emissions control system is a fault, which means you are polluting more than usual. Bring the car to your mechanic for a proper diagnostic, it may save you from more expensive damage later on. Car Modifications After-market performance modifications abound in some types of cars – louder exhaust pipes, modified air intakes, reprogrammed fuel injection. All those features increase your engine’s fuel needs, so get rid of them or better yet don’t install them in the first place. Larger tires and suspension lifts need to go too. Roof racks and cargo boxes should be put away when not in use, as they severely affect fuel economy, especially on smaller cars. Empty your car trunk too, as it takes extra fuel to carry around that golf bag you never have time to get out, or those crates of books you’ve been meaning to drop off at the thrift store. What’s Your Driving Style? Driving behavior is another place where you can make a big difference in your emissions and fuel use without spending any money. Slow down: according to AAA, going 60 mph instead of 70 mph on a 20-mile commute will save you 1.3 gallons on average over the work week. Accelerate and stop gently, and coast while you can. Keep your windows up to reduce drag; even running the air conditioning requires less energy. Letting your car idle in the morning is unnecessary, uses fuel, and produces useless emissions. Instead, gently warm up your engine by accelerating smoothly and keeping a lower speed until your car reaches its operating temperature.