Applications of Titration Essays - Bases, Sodium Compounds

Applications of Titration Essays - Bases, Sodium Compounds Applications of Titration November 27, 2015 December 2, 2015 S. Raphael Introduction: The laboratory method used in this experiment is titration. Titration can be traced back to the start of volumetric analysis, in the late eighteenth century. The study of analytical chemistry began in France (Bandos, 2015). The first burette was made by Francois Antoine Henri Descroizilles, a French chemist and pharmacist (Rosenfeld, 1999). The field began to spread to other European countries. The first text that mentioned titration was published in 1855 in Germany. It was titled Lehrbuch der chemisch-analytischen Titrirmethode (Instructional Book of Titration Methods in Analytical Chemistry). Karl Freiderich Mohr, the author of the book, is also responsible for advancing the burette from an inefficient graduated cylinder-type instrument to a tool with a clamp at the bottom that is still used today (Bandos, 2015). Titration is a laboratory technique that is used to determine the concentration of solution by reacting the known volume of that solution with the measured volume of a sol ution with a known concentration (Haberer et al., 2011). To determine concentration, the equation for concentration in relation to moles and volume is used. C=n/V C= concentration in mol/l n= moles in mol V= volume in L (Ms. Raphael, SCH 3U1, November 29, 2015). Molarity (M) or molar concentration is the unit used for expressing the concentration of solutions. It is defined as the number of moles of solute per liter of solution (Chemteam.info, 2015). To be categorized as an acid according to Arrhenius Theory, the solution must be able to form hydrogen ions when dissolved in water. To be categorized as a base according to Arrhenius Theory, the solution must be able to form hydroxide ions when dissolved in water (France, 2015). To be categorized as an acid according to Bronsted-Lowry Theory, the solution must be able to donate a proton, a hydrogen ion, to a base. To be categorized as a base according to Bronsted-Lowry Theory, the solution must be able to receive a proton, a hydrogen ion, from an acid (Williams, 2015). In both theories the acid must be an aqueous solution, be able to neutralize a base, and have a pH of less than 7. As well as a base must be an aqueous solution, be able to neutralize a base, and have a pH of greater than 7 (Chemtutor.com, 2015). In a titration, one reagent, the titrant, is slowly added to another, the titrate. In titration, the titrant is the solution with the known concentration, the titrate is the solution with the unknown concentration (Dartmouth.edu, 2015). In the experiment the titrant, sodium hydroxide, was diluted with distilled water to create a 0.5mol/L NaOH solution. The amount of distilled water need to dilute the base was calculated using the formula for dilution, which was rearranged. C1V1=C2V2, rearranged to solve for V1, V1= C2V2/ C1 C1=original concentration of solution C2=final concentration of the solution V1=original volume of the solution V2=final volume of the solution (Ms. Raphael, SCH 3U1, November 29, 2015). As the reagents are added to one another, using a burette, a chemical stoichiometric reaction occurs until the limiting reagent is exhausted. An indicator is used to distinguish when this happens. A burette is a clear tube with volume markings along its length and a tap at the bottom. The indicator changes colour when the end-point has been reached, which is at the point of neutralization (Richards Fromm, 2015). In the experiment phenolphthalein was used as an indicator. Phenolphthalein is a commonly used indicator in titrations. It is an acid-base indicator which is colourless when in acid solution, and turns pink to red as the solution becomes more basic (Pubchem.ncbi.nlm.nih.gov, 2015). To determine the pH of the solution, the equation to solve for pH was used. pH=-log[H3O+] pH= acidity or alkalinity of solution [H3O+]= concentration of solution (Ms. Raphael, SCH 3U1, November 29, 2015). The purpose of titration is to find the point at which the moles of the standard solution is equal to the moles of the unknown solution, this is known as the equivalence point (Clark, 2015). The mole is an SI unit, Systme International d'Units, which measures the number of particles in a given substance. One mole is equal to 6.02 x 1023 atoms, or other appropriate units

Free Essays on Heroes Or Not Lesson Before Dying

Heroes or Not: A Lesson Before Dying In Gaines’ novel A Lesson Before Dying, the reader is presented with a group of black people, dealing with racism, and struggling to help each other find peace. Throughout the book, the main character, Grant, has been assigned the duty of raising the self-esteem of a young man named Jefferson, who has been sentenced to death. It is the wish of Jefferson’s grandmother Emma that Jefferson should die as a man. In the end, Grant does succeed in helping Jefferson feel like a man, and some will consider him a hero for doing this. After reflecting on the story, and looking at Grant’s own definition of a hero, it becomes apparent that this novel is full of heroes. In the book, Grant describes a hero in this manner: A hero is someone who does something for other people. He does something that other men don’t and can’t do. He is different from other men. He is above other men. No matter who those other men are, the hero, no matter who he is, is above them (A Lesson Before Dying 193). Grant gave this definition of a hero to Jefferson, while trying to make Jefferson feel like more of a man. Jefferson, a young black man with little education, has been sentenced to death for the murder of a white storeowner. During the trial for this murder, Jefferson’s lawyer attempts to convince the court that Jefferson was too dumb to commit this type of crime, and goes on to describe Jefferson as a hog. This is why Jefferson has lost his sense of manhood, and believes himself to be an animal. Now we will examine the heroism of the novel. In my opinion, the first hero we meet is Jefferson’s grandmother Emma. This elderly black woman is near the end of her days, yet she still realizes the need for her grandson to be a man when he goes to meet his Maker. Even though she is fully aware that Grant will be against the mission of making Jefferson a man, she still asks him to do it. She a... Free Essays on Heroes Or Not Lesson Before Dying Free Essays on Heroes Or Not Lesson Before Dying Heroes or Not: A Lesson Before Dying In Gaines’ novel A Lesson Before Dying, the reader is presented with a group of black people, dealing with racism, and struggling to help each other find peace. Throughout the book, the main character, Grant, has been assigned the duty of raising the self-esteem of a young man named Jefferson, who has been sentenced to death. It is the wish of Jefferson’s grandmother Emma that Jefferson should die as a man. In the end, Grant does succeed in helping Jefferson feel like a man, and some will consider him a hero for doing this. After reflecting on the story, and looking at Grant’s own definition of a hero, it becomes apparent that this novel is full of heroes. In the book, Grant describes a hero in this manner: A hero is someone who does something for other people. He does something that other men don’t and can’t do. He is different from other men. He is above other men. No matter who those other men are, the hero, no matter who he is, is above them (A Lesson Before Dying 193). Grant gave this definition of a hero to Jefferson, while trying to make Jefferson feel like more of a man. Jefferson, a young black man with little education, has been sentenced to death for the murder of a white storeowner. During the trial for this murder, Jefferson’s lawyer attempts to convince the court that Jefferson was too dumb to commit this type of crime, and goes on to describe Jefferson as a hog. This is why Jefferson has lost his sense of manhood, and believes himself to be an animal. Now we will examine the heroism of the novel. In my opinion, the first hero we meet is Jefferson’s grandmother Emma. This elderly black woman is near the end of her days, yet she still realizes the need for her grandson to be a man when he goes to meet his Maker. Even though she is fully aware that Grant will be against the mission of making Jefferson a man, she still asks him to do it. She a...

Museum paper- art history Essay Example | Topics and Well Written Essays - 1000 words

Museum paper- art history - Essay Example These types of images were giving way to more humanist styles in forms of expression as images were depicted in a more optical style. These changes can be seen when comparing pottery currently on display at the Boston Museum of Fine Arts, such as the Panathenaic prize vase and the Amphora Depicting Oedipus and the Sphinx of Thebes. There are numerous similarities between these two objects, but with approximately 100 years between manufacture, stylistic differences are also evident. Both objects are classified as amphora, which was a type of two-handled urn that was often used to carry wine or water. These types of vessels were often decorated with scenes from heroic stories and mythology as in the image of Oedipus talking with the Sphinx in the later example (Skaar, 2006). This ceramic amphora was made in the red figure style in the city of Athens sometime between 450-440 BC by the Achilles painter. It stands approximately 13 inches high and is approximately 6  ½ inches in diameter at its widest point near the center (Bostom Museum). Despite the tradition, though, the earlier example seems to be more of a commemorative piece as it depicts five stylized runners and is marked with the words â€Å"of the prizes from Athens† (Boston Museum). This amphora is also ceramic and created in Athens, but is made in what is called the black figure style approximately 100 years earlier between 530-520 BC by the Euphiletos Painter. It stands approximately 24 inches tall and measures approximately 16 inches around at its widest point near the top (Boston Museum). Both vases have some damage as a result of time. The Prize vase shows some signs of damage and attempts at restoration while some of the pigment for the Oedipus amphora has worn away leaving some of the story of the vase up to science and history. The museum’s assessment of these pieces seems largely correct.