• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

Determining the identity of an organic unknown

Extracts from this document...

Introduction

Assessed practical Debbie Siobhan Warner November 2002 Determining the identity of an organic unknown When supplied with a organic unknown there are many ways of determining its identity and it is important to use as much information as can be gained to work out the identity of an unknown as many are very similar in physical properties, chemical properties and/or chemical make up. In this experiment I will be using a flow chart to identify the functional group that the unknowns contain, and once I have suggested this I will then use spectra given to me to determine what the identity of the organic unknown is. I have been told that the organic unknown, will one of the following functional groups: Alcohol's Probably the most common of these functional groups is the "-OH" group, which is known as the hydroxyl group. It is NOT the hydroxide ion, OH1-, as it does not have a charge. The dash in front of the OH stands for a single covalent bond, which is what will be formed between the oxygen and a carbon atom. An aliphatic hydrocarbon that has one hydroxyl group attached to a carbon is called an alcohol. ...read more.

Middle

Ants inject formic acid into their victim whem they bite them. The next in line is, of course, ethanoic acid, CH3COOH. Notice the ending, -oic, to the IUPAC name, and -ic, to the common name. There are some very important organic acids, and one of the most important is ascorbic acid, better known as Vitamin C. The generic formula is R-(COOH)x Why are these compounds acids? Well, they must be able to produce at least one hydrogen ion when they are put into solution, since that is the general definition for an acid. Even though these organic acids may contain quite a few hydrogen atoms in the molecule, only select hydrogens are able to be "ionized" or turned into hydrogen ions. These "select" hydrogens are those in the carboxyl group (-COOH) The presence of one or more of these groups, therefore, causes the compound to belong to the organic acids. Ester An ester results when there is an oxygen atom between two carbons in the chain. The simplest is dimethyl ester, which has the same molecular formula as ethanol. The way the formula is written to show the ester, rather than the alcohol, is CH3OCH3. There are two other esters of interest, ethylmethyl ester and diethyl ester. ...read more.

Conclusion

This is because not only does its physical properties fit those described in text books it also has the right structural formula to fit with the spectropic data provided. benzaldehyde benzaldehyde or benzenecarbonal , C6H5CHO, colourless liquid aldehyde with a characteristic almond odour. It boils at 180�C, is soluble in ethanol, but is insoluble in water. It is formed by partial oxidation of benzyl alcohol, and on oxidation forms benzoic acid. It is called oil of bitter almond, since it is formed when amygdalin, a glucoside present in the kernels of bitter almonds and in apricot pits, is hydrolysed, e.g., by crushing the kernels or pits and boiling them in water; glucose and hydrogen cyanide (a poisonous gas) are also formed. It is also prepared by oxidation of toluene or benzyl chloride or by treating benzal chloride with an alkali, e.g., sodium hydroxide. Benzaldehyde is used in the preparation of certain aniline dyes and of other products, including perfumes and flavourings. Evaluation Overall I feel this experiment went very well as I was able to determine both the functional group present and then with the aid of specropic data the exact compound. I carried out the experiment safely following all guideline set in my method. The only test that could have been performed more accurately was the test for an alderhyde that did not produce a silver mirror. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Physical Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Physical Chemistry essays

  1. Investigating the Rate of the Reaction between Bromide and Bromate Ions in Acid Solution

    Put on safety goggles 2. Measure out using a burette the volumes of solutions required into beaker X and beaker Y (see tables 2.4.1 to 2.4.3 below method giving details of what volumes of each solution are required when varying the concentration of each reaction)

  2. Identification of an Organic Unknown

    I will be wearing safety goggles because the acid and phenol are very corrosive. If there is a 'pop' I known that it could be one of, an alcohol, phenol or carboxylic acid. I can now split the route into two and from what I discover from the first experiment I can take either one of the routes.

  1. Electrochemistry - Inventing Better Batteries

    The energy aspect is also related to the chemical equilibrium. All these relationships are tied together in the concept of Nernst equation. The maximum potential difference is called the electromotive force (EMF). The Nernst equation also indicates that you can build a battery simply by using the same material for both cells, but by using different concentrations.

  2. Investigating how concentration affects rate of reaction

    This ensures that the test is fair. This is an accurate method as it is simple and therefore it is easy to avoid mistakes. I did not need to take a series of measurements throughout the reaction, which increases the chances of human error.

  1. Antacid Lab. Are name brand antacids better than generic brand antacids to neutralize ...

    Put on safety goggles. 2. Gathered the tools and ingredients needed to perform the experiment. 3. Calibrated the pH probe using the buffer solutions pH 2 and 11. 4. Set up a graph and table on the program to record observations.

  2. Analysing Dyes Through Gel Electrophoresis

    Since the 1940?s, major changes have been made to electrophoresis which lead to a variety of new methods. Today, there are numerous gels that are used, for instance, Agarose, Polyacrylamide and Starch. The gel that was used in this experiment was agarose gel because of its easy casting and the simple recovery of remaining fragments.

  1. Chemistry Lab: Classifying Unknown Substances

    Trial 2 time (s) Trial 3 time (s) Trial 4 time (s) A 30 31 40 32 B 38 46 37 38 C 32 31 25 30 During this test, all the substances seemed to take a similar time to dissolve. However, when stirring, substance A seemed to disperse and have just a few granules left floating around until they dissolved.

  2. Individual investigation - Reaction to be studied Rate of reaction between propanone and ...

    But when adding the propanone (colourless) and hydrochloric acid (colourless), the colour slightly became lighter orange. As we transfer the mixture (iodine-HCL-propanone) into the conical flask (contains Sodium hydrogen carbonate), colour doesn't change but the carbon dioxide gas is formed because mixture was producing bubbles.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work