Titration Lab
The Mass of Acetylsalicylic Acid in Aspirin
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Purpose
The purpose of the lab is to determine the mass of the ‘active ingredient’ in a commercial ASA tablet.
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Introduction
There are three main theories surrounding acids and bases including the Arrhenius, Bronsted-Lowry, and Lewis theories. The Arrhenius theory of acids and bases states that acids produce hydrogen ions (H+) in solution while bases produce hydroxide ions (OH-) in solution. Arrhenius was able to determine his theory based on his prior knowledge of the behaviour of substances in aqueous solution. Arrhenius went further to describe strong acids as a strong electrolyte that was able to ionize completely in order to give hydrogen ions in aqueous solutions. However weak acids can only ionize partially, remaining moderately in molecular form. Similarly, a strong base is also a strong electrolyte that ionizes completely to release hydroxide ions in aqueous solution while weak bases only partially ionize. The Arrhenius theory is specifically deals with acid-base reactions in water. The second theory, intends the contemporary ‘protonic’ or Brownsted-Lowry theory of acid-base behaviour. This theory states that an acid is a compound or ion that can give up a proton however a base is a compound or ion that accepts a proton. Water is amphiprotic because water can give up and accept proton depending on the reaction. Water gives up a proton to form hydroxide ions (OH-) but water accepts a proton to form hydronium ion (H3O+). The Bronsted-Lowry theory is just an addition to the Arrhenius theory in term of all Arrhenius bases that are sources of hydroxide will accept protons. Bronsted-Lowry theory also coincides with the ability for ammonia and amines to accept protons to form ammonium ions and it can also be applied to reactions that involve solutions that do
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Purpose
The purpose of the lab is to determine the mass of the ‘active ingredient’ in a commercial ASA tablet.
-------------------------------------------------
-------------------------------------------------
Introduction
There are three main theories surrounding acids and bases including the Arrhenius, Bronsted-Lowry, and Lewis theories. The Arrhenius theory of acids and bases states that acids produce hydrogen ions (H+) in solution while bases produce hydroxide ions (OH-) in solution. Arrhenius was able to determine his theory based on his prior knowledge of the behaviour of substances in aqueous solution. Arrhenius went further to describe strong acids as a strong electrolyte that was able to ionize completely in order to give hydrogen ions in aqueous solutions. However weak acids can only ionize partially, remaining moderately in molecular form. Similarly, a strong base is also a strong electrolyte that ionizes completely to release hydroxide ions in aqueous solution while weak bases only partially ionize. The Arrhenius theory is specifically deals with acid-base reactions in water. The second theory, intends the contemporary ‘protonic’ or Brownsted-Lowry theory of acid-base behaviour. This theory states that an acid is a compound or ion that can give up a proton however a base is a compound or ion that accepts a proton. Water is amphiprotic because water can give up and accept proton depending on the reaction. Water gives up a proton to form hydroxide ions (OH-) but water accepts a proton to form hydronium ion (H3O+). The Bronsted-Lowry theory is just an addition to the Arrhenius theory in term of all Arrhenius bases that are sources of hydroxide will accept protons. Bronsted-Lowry theory also coincides with the ability for ammonia and amines to accept protons to form ammonium ions and it can also be applied to reactions that involve solutions that do
Bibliography: 1. "Aspirin." Apuntes, Trabajos, Exámenes, Prácticas y Otros documentos. N.p., n.d. Web. 28 May 2010. <http://html.rincondelvago.com/aspirin_1.html>. 2. "Neutralization reaction." Connexions - Sharing Knowledge and Building Communities. N.p., n.d. Web. 28 May 2010. <http://cnx.org/content/m17138/latest/>. 3. "Phenolphthalein." Digipac Microcomputer Software. N.p., n.d. Web. 28 May 2010. <http://digipac.ca/chemical/equilibrium/phenolpthalein.htm>. 4. "Titration." An Introduction to Chemistry - Bishop. N.p., n.d. Web. 28 May 2010. <http://chiralpublishing.com/Bishop_Titration.htm>. 5. stander. "Acids and Bases." Chemistry and New Zealand. N.p., n.d. Web. 28 May 2010. <http://www.chemistry.co.nz/acids_and_bases.htm>.