Concentration of HCL affecting surface area to vol ratio Essay Example for Free

Concentration of HCL affecting surface area to vol ratio Essay The research question that this report is going to discuss is â€Å"What is the relationship between concentration of hydrochloric acid (HCl) and the rate of diffusion? † My hypothesis for this research question is that change in rate of diffusion will be observed when the agar blocks are placed in solutions of different concentrations of HCl. As the concentration of HCl increases, the rate of diffusion will also increase due to the steeper concentration gradient created. To investigate the change in rate of diffusion when different concentrations of HCl are used, I used agar blocks that are stained with universal indicator that would change from green to pink when exposed to HCl. To prepare the agar blocks, I used knife and ruler to acquire 5 agar blocks with equal dimensions of 3. 0cm by 1. 0cm by 0. 5cm. Then I prepared 5 different concentrations of HCl with equal volume of 5cm^3 in test tubes, which were 0. 0M. 0. 2M, 0. 4M, 0. 6M, 0. 8M and finally 1. 0M of HCl. Then, I placed the agar blocks into respective test tubes, measuring the time taken for the agar blocks to turn from green to completely pink. This was repeated 2 more times, having 3 set of readings in total. The results collected showed an increasing trend in the rate of diffusion as the concentration of HCl increased. This clearly supported the hypothesis I derived at. (227 words) ? Content Page Abstract2 Content Page3 Introduction4 Research question:4 Hypothesis:4 Introduction (2)5 Literature Review5 Methodology6 Results8 Results (2)9 Discussion10 Limitations11 Improvements11 Conclusion12 Bibliography13 ? Introduction Research question: How does change in concentration of hydrochloric acid (HCl) affect the rate of diffusion through the agar blocks which contain starch stained with universal indicator, while keeping surrounding temperature, the surface area to volume ratio of agar blocks used and the volume of solution to which the agar blocks were placed constant? Hypothesis: Change in rate of diffusion will be observed when agar blocks are placed in solutions of different concentrations of HCl. As the concentration of HCl increases, the rate of diffusion will also increase due to the steeper concentration gradient created ? Introduction (2) Literature Review Diffusion is known as the net movement of particles from a region of higher concentration to a region of lower concentration along the concentration gradient. There are few factors that affect the rate of diffusion, the time taken for both regions to have equal amount of particles. One of them is temperature. It is known that temperature has the greatest effect on diffusion rates and is the easiest of the factors to change. Increasing the temperature increases the diffusion rate by adding energy to each particle. This is because particles with more energy can move to the region of lower concentration with more speed and more easily. Similarly, lowering the temperature will lower the diffusion rate by lowering the energy of each particle. Another important factor that changes the rate of diffusion is the concentration gradient, which we will be exploring in this experiment. The rate of diffusion depends on the difference between concentrations across the region of lower concentration and higher concentration, with steeper concentration differences resulting in higher diffusion rates (Simon 2013). This can be explained by Fick’s Law, which can be summarised by this equation: Rate of diffusion is proportional to(surface area x difference in concentration )/(Length of diffusion path). From the equation derived from Fick’s Law, it is clearly seen that the difference in concentration (concentration gradient) will increase the rate of diffusion (Michael Kent 2000). This theory can be used to explain real life situations, like how human lungs take in oxygen and give out carbon dioxide in a split second. It is due to the great difference in concentrations of both gases (very steep concentration gradient) that allows relatively fast rate of diffusion. For instance, when breathing in, the concentration of oxygen in alveoli is very high compared to that in the blood vessels surrounding the alveoli. Thus, rate of diffusion is great, allowing oxygen to diffuse as fast as possible. (BBC 2013) Methodology Table 1.1-Table of variables and how it is controlled VariablesDetails of variablesHow it is controlled Independent VariableConcentration of HClConcentration of HCl is controlled by the amount of distilled water added to HCl. For example, in order to achieve a concentration of 0. 2 moldm^(-3), 1. 0 cm^3 of 1 mol of HCl is added, with 4 cm^3 of distilled water added. Dependent VariableRate of Diffusion The time is taken by a stopwatch until the agar blo ck turns pink in colour completely. Controlled VariableTemperature of the surrounding Surface area to volume ratio of the agar blocks Volume of solution to place the agar blocks into. Temperature is set at an air-conditioned room in a Biology lab The agar blocks are cut into same length, same breadth and same height (3. 0 cm by 1. 0 cm by 0. 5cm), thus having the same volume and surface area. This ensures the ratio is the same. The volume of solutions used is kept the same at 5. 0cm^3. Table 1. 2-Apparatus used in the experiment Apparatus QuantityUncertainty 2% Starch Agar (Universal Indicator stained) 1. 0 M Hydrochloric Acid (aq) Deionized Water Stop Watch2 ±0. 01s This might be due to the inaccurate cutting of the dimension of the agar blocks. It could also be due to our inability to decide whether the agar blocks have turned completely green to pink in colour. Thus, the calculated rate of diffusion could have changed. Limitations Some of the results were not as accurate as it was difficult to see whether the agar blocks have turned entirely pink in colour. Some of the agar blocks still had strips of green in them when we removed it from the solution and cut it. This could have affected the time taken for the agar blocks to turn entirely pink and thus, affecting the rate of diffusion. The temperature of the solutions containing the agar blocks might not be constant throughout the whole experiment. This can be due to holding of test tubes with our hands and also putting it down again several times. The heat from the hand might get transferred and the temperature might be altered. This can affect the time taken for the agar blocks to turn completely pink, as higher temperature induce faster rate of diffusion. Some of the results are not very accurate as the surface area to volume ratio was not constant for all the agar blocks tested. One of the reasons is due to the limited amount of agar blocks that were allocated for each bench. Another reason is that it was difficult to use the knife provided to cut the agar blocks in a straight manner and as accurately. This limitation can affect the time taken for agar blocks to turn pink, followed by the rate of diffusion, as some blocks are bigger while some are smaller than the others. Improvements In order to make sure that the agar blocks have turned entirely pink, use a light and put it in a white background where the colour changed is more visible. Then, the calculated rate of diffusion will not be affected. Place the test tubes in a water bath where the temperature can be kept constant at the temperature of tap water. This way, the calculated rate of diffusion will not be affected. Lastly, use a stamp with all the desirable dimension of the agar blocks measured. This way, not only is it convenient, it also helps us acquire the accurate dimensions of the agar blocks, having the same surface area to volume ratio for all the agar blocks. Then, the calculated rate of diffusion will not be affected. Conclusion In conclusion, the readings and the derived results in the form of tables, and line graph support my hypothesis, which is: Change in rate of diffusion will be observed when agar blocks are placed in solutions of different concentrations of HCl. As the concentration of HCl increases, the rate of diffusion will also increase due to the steeper concentration gradient created. With the derived conclusion, it shows that in order for rate of diffusion to be greater, higher concentration of the solution must be used, so that the concentration gradient is steeper.

Essay --

The Shaping’s of Jane Eyre Zucaru Ruth 2/21/2014 2nd period In life the people around Jane Eyre has a way of shaping her as a person. As a person grows older, weather very negative or positive it makes a stronger person out of a person or it affects that person in some way in life. Unfortunately and sadly for Jane she had horrible and wicked people in her life as she grew to be a young woman. Luckily for Jane, down the line of life she was able to meet those whom was respectful to her and appreciated her help and servant abilities. Multiple people had an effect on shaping Jane as a person. By the end of this essay it will be proven that the person in Jane’s life has shaped her Social drive and development as a young woman succeeding its also will be proven on the affects of Jane Eyre and bildungsroman life and early figures in feminist movement, with the affects of Jane’s life and thoughts. â€Å"The night as Jane lays there thinking about everything Mr. Rochester has told her, when she thinks she hears a â€Å"demoniac† laugh. When she leaves her room she then finds a candle burning in the hallway. Jane sees Mr. Rochester’s door open and finds his curtains on fire. He is stupefied by Smokey air, but she wakes him by extinguishing the flames and dousing him with water†, chap 15. Then the actions that took place puts Mr. Rochester in a position of vulnerability as Jane douses water in Mr. Rochester’s room. The situation allows to show her growth as a grown woman in control and independent. The situation brings Mr. Rochest... ...eople in her life has also shaped her to feel extreme tension for the characters around her. Although it’s very fortunate that an orphan like Jane her self is able to achieve wealth and power without having education or social motivation , Jane also has manners and shows sophistication while remaining penniless and powerless. A person cannot always makes choices for themselves in life, some people are put into a life or a situation that has to be shaped its self, negatively or positively. The drive and motivation a person takes from certain situations weather negative or positive in life it shapes a persons character and focus. This essay has proven that the people in life can shape aspects of a person’s future and drive as well as motivation. It has also has proven on the effects of early figures in feminist movement ,with the affects of Jane’s life and thoughts.

Recommended Policies to Achieve a Sustainable Society Essay

Italy has been faced with fact that they are the second country with the lowest birth rate next to Spain. There are multiple recommendations that may be done in order to keep Italy up and running. One recommendation would be Italy may want to look at why France and Ireland have a high rate of child birth to help keep them up and running in the game of population. Other countries like France and Ireland give their people benefits for having children. Italy may want to take a look into bribing their people into having children. Maybe Italy should offer funding for health care, child care, and also offering higher incentives to families with more than one child. Italy’s incentive rate right now for a woman giving birth to a second child is only 1000 Euros. Italy should offer their people these benefits in order to help Italy’s low birth rate, here are the reasons why. Italy is the second country that has the lowest birth rate in the nation, with only one child per female. One might recommend that Italy might want to look into France and Ireland because they have the second highest birth rate in Europe. If Italy looks into France they might find out in that country they actually pay families for having children (Dillinaco, 2004-2008). In French families are entitled to up to three years paid maternity leave with a guarantee that mom’s job will be there for her when she returns. If Italy does that maybe the woman there wouldn’t be so scared on having children. Their burden of having to find a new job after giving birth or if their job will still be there will be lifted off their shoulders. A new law provides greater maternity leave benefits, tax credits and other incentives for families who have a third child. During a year-long leave after the birth of the third child, mothers will receive $960.00 a month from the government, twice th e allowance for the second child. France shows that they take care of the moms even after they give birth by paying them for three years to be with their children (Conroy, 2011). France is a great place to learn from when trying to raise the low birth rate. On top of giving their people money for having children they also help them cover some of their childcare costs so the country can establish a good birth rate in order to keep their population going. France was smart and know that they couldn’t just pay women and that will be enough for them. France knows that the women will need help with childcare also. So, the government decided to covers some child-care costs of toddlers up to 3 years old and offers free child-care centers from age 3 to kindergarten, in addition to tax breaks and discounts on transportation, cultural events and shopping. Their plan worked so well that the municipal day-care center ran out of space because of a local baby boom. In fact, they actually gave families an extra $100.00 per kid if the parents took care for their own child (Sensing, 2006). France really knows how to convince their people into having babies. Paying mothers maternity leave and making sure their job is still there when they return is a great way to encourage women to have children. Not only will the mothers get paid maternity leave, it is paid maternity leave for three years. France will also help the mothers pay for childcare if the mother decides to return back to work before the three years is up. After the child makes three years old and the mother goes back to work the child care is then free from ages three to kindergarten. On top of free childcare France also pays their people $960.00 a month as long as they have three or more children, which is twice as much as two children. If Italy took care of the mothers like France does, they just might have a higher birth rate. Conroy, S. (2011, February 11). Bonuses for having babies in france. Retrieved from http://www.cbsnews.com/stories/2006/12/10/eveningnews/main2243958.shtml Dillinaco, D. (2004-2008). Low birth rates in italy. Retrieved from http://mommiesonline.net/health/low-birth-rates.php Sensing , D. (2006, October 20). Paying women to have children. Retrieved from http://www.windsofchange.net/archives/paying_women_to_have_children.html

Differences and Similarities Between The Little Shop of Horrors and Macbeth - Free Essay Example

Sample details Pages: 2 Words: 737 Downloads: 5 Date added: 2019/02/20 Category Literature Essay Level High school Tags: Macbeth Essay Did you like this example? Have you ever watched The Little Shop of Horrors or read Macbeth? The Little Shop of Horrors is an entertaining film from the 1960s about a deficient florist that invents a people-eating plant. Macbeth is a tragedy about a general that becomes consumed with the idea of holding power in the Kingdom of Scotland. The Little Shop of Horrors and Macbeth are different regarding the time periods that each story is set in and the quality of each script, but are similar by using death in an attempt to be successful. The first difference between The Little Shop of Horrors and Macbeth is the time periods that each story takes place in. The Little Shop of Horrors transpires in the 1960s. During that time, fashion and conversation were more modernized than that displayed in Macbeth. Individuals dressed in clothing similar to what is worn presently. Men, especially Mr. Mushnick and Seymour, wear nice shirts and slacks while women such as Audrey wear dresses, nice tops, and skirts. The characters converse using the same vocabulary that individuals use today. Macbeth, on the other hand, is set in the Renaissance and Elizabethan Eras. During that time in history, fashion and vocabulary were very formalized. Males like Macbeth, Banquo and his son, and Duncan and his sons dress in nice shirts, blazer coats, and knee-length trousers. Females such as Lady Macbeth and Lady Macduff wear gowns with fitted bodices and fuller skirts. Their choice of vocabulary is intricate and resembles Old English. Words like à ¢â‚¬Å"whence,† â€Å"hath,† and â€Å"thou† are used frequently. Don’t waste time! Our writers will create an original "Differences and Similarities Between The Little Shop of Horrors and Macbeth" essay for you Create order The second difference between The Little Shop of Horrors and Macbeth is the quality of each script. The Little Shop of Horrors is a poorly written and performed film. The screenwriters were drunk and wrote the movie in one day and then had it completely filmed in two days. The screenplay includes a human flesh-eating plant, Audrey Junior, which often shouts â€Å"Feeeeed meeeee.† As a result, Seymour, an employee at Mr. Mushnick’s flower shop, murders three individuals to feed to the plant. During the Sixties, though, B movies were very popular. Therefore, it is no surprise that the script and acting is worse than what one would see on television today. Compared to The Little Shop of Horrors, Macbeth is a very well written play. In fact, it was written by William Shakespeare, one of the greatest writers in the English language. During Shakespeare’s time, comedies, tragedies, and histories were common plays to be performed. Accordingly, the playwright wrote the cl assic tragedy, Macbeth. The play’s plot is structured and thorough. It begins with Macbeth receiving a prophecy from the three witches stating that he will reign as the King of Scotland one day. Next, he realizes that their prediction may indeed be correct. Then, several other individuals become involved and people who threaten Macbeth’s position in the kingdom are murdered. In the end, Macbeth notices that he misinterpreted the prophecy and is murdered by Macduff. Despite the differences between The Little Shop of Horrors and Macbeth, there is a similarity within each script – the characters use death in an attempt to be victorious. In The Little Shop of Horrors, Mr. Mushnick’s flower shop’s success depends on Seymour’s new plant, Audrey Junior, which he names after his crush and Mr. Mushinick’s daughter, Audrey. Once again, the plant feeds off of human flesh and blood and is very demanding. As a result, Seymour is persuaded to kill a dentist, a railroad detective, and a promiscuous woman in order to help Audrey Junior continue to survive and attract more customers. As has been stated, in Macbeth, the Scottish thane is told that he will be the King of Scotland one day. He is skeptical of that prediction until he is triumphant in battle. Then, Macbeth either kills or has several individuals murdered who he thinks is an ultimatum to his rank. In spite of each of the main character’s endeavors to be succe ssful, Seymour and Macbeth are both dead at the finish of each script. To conclude, The Little Shop of Horrors and Macbeth are different regarding the time periods that each story takes place in and the quality of each script, but are similar by striving to be victorious using death. Watching this film or reading this play would be an exceptional pastime for any individual and would certainly leave one speechless.