Classification Tests for Carboxylic Acid and Derivatives
Mary Catherine Sarte, John Emmanuel Sy, Allurie Umel,Franklin Yap,
Mary Christine YouIntroduction Carboxylic acids derivatives are simply groupsof compounds that contain a carbonyl group butwith an electronegative atom attached to thecarbon. The difference in the structure leads to amajor change in reactivity. The reactions of thesegroups of compounds involve nucleophilicsubstitution. Although there are abundant kindsof carboxylic acid derivatives, the experimentonly focuses on the common ones: acid halides,acid anhydrides, esters and amides.Carboxylic acids and their derivatives areusually seen in industrial processes and mostbiological pathways. Esters can be seen as fatsand
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Reactions of carboxylic acides also yield esters, salts and acyl chlorides. The experiment done isto test whether the substance is positive for carboxylic acid and derivatives. The reagents used are acylchloride representing acyl halides; acetic anhydride representing acid anhydrides; ethyl acetaterepresenting esters and acetanamide and benzamide representing amides. Specific tests were performed tospecific compounds. Yielding a positive results indicate the presence of the carboxylic acid group.
In another test tube, a mixture of 0.5mlethanol, 1ml water, and 0.2ml of acyl halide oracid anhydride was prepared. 2ml of 20% NaOHsolution was then added. The test tube wascovered with paraffin wax and was shook forseveral minutes. An odor of the formed ester anda formation of two layers were noted.
C.Aminolysis: Anilide Formation
A few drops of acetyl chloride or aceticanhydride was added to 0.5ml of aniline. Themixture was transferred to a new test tubecontaining 5ml water. The formation of aprecipitate was noted.
D.Hydroxamic Acid Test
The preliminary test was done by mixing 2drops of the sample, 1 ml of 95% ethanol and 1MHCL. A drop of 5% FeCl
3
solution was added tothe mixture and the color produced was noted. If a color other than yellow was obtained, the testcannot be used. Otherwise, another test wasconducted as follows:2 drops of the sample was added to 2ml of alcoholic NH
2
OHHCL and 1ml of KOH. Thesolution was heated in a boiling water bath for
You know what color phenolphthalein and BTB turn when testing an acid or a base. Use three household cleaning products with BTB. Name the items tested and their results:
Perform the following with three 0.05g samples of unknown and the following solvents: methanol, water and toluene
However, to form amides a more efficiently anhydride and amine react, this in result creates an amide and carbocyclic acid. Esters and amides have similar structures and are both produced by reaction with amine, but amides and esters are very different in their chemical and physical properties. Amides unlike esters can form hydrogen bonds and therefore typically have higher melting points and are typically being pH neutral. In this part of the experiment, 4-aminophenol(1g) and acetic anhydride(1.25ml) will react with water to synthesize acetaminophen. In the
The primary goal of this laboratory is to correctly identify an unknown substance. To achieve this task, one may use various tests that reveal both chemical and physical properties of a substance. By comparing the results of a known substance and the unknown substance, one may eliminate alternative possibilities and more accurately predict the undisclosed compound. Furthermore, by performing these tests, data can be collected and verified regarding chemical and physical properties of the unknown. Understanding the chemical properties of a known substance aids one’s understanding of the unknown based on comparative analysis of the results of the tests.
Salicylic acid was esterfied using acetic acid and sulfuric acid acting as a catalyst to produce acetylsalicylic acid and acetic acid. The phenol group that will attack the carbonyl carbon of the acetic anhydride is the –OH group that is directly attached to the benzene since it is more basic than the –OH group attached to the carbonyl group. This method of forming acetylsalicylic acid is an esterification reaction. Since this esterification reaction is not spontaneous, sulfuric acid was used as a catalyst to initiate the reaction. Sulfuric acid serves as the acid catalyst since its conjugate base is a strong deprotonating group that is necessary in order for this reaction to be reversible. The need for the strong conjugate base is the reason why other strong acids such as HCl is not used since its conjugate base Cl- is very weak compared to HSO3-. After the reaction was complete some unreacted acetic anhydride and salicylic acid was still be present in
9-anthraldehyde and (carbethoxymethylene)triphenylphosphorane were reacted together using the Wittig reaction to produce E-3-(9-Anthryl)-2-propenoic acid ethyl ester. .100 g of 9-anthraldehyde and .180 g of (carbethoxymethylene)triphenylphosphorane were used. 9-anthraldehyde was a green powder while (carbethoxymethylene)triphenylphosphorane was a white powder. Both were added together into a 3.00 mL conical vial with a magnetic spin valve. The vial was inserted into a 120 C sand bath to melt the reagents. Once the reagents melted, they were stirred for 15 minutes (2:30 pm-2:45 pm). After stirring, the vial was removed to cool to room temperature. 3.00 mL of hexanes were added to the vial and the suspension was stirred. The solvent was removed
items presently in solid form in the lab kit or purchased separately for this laboratory
The purpose of this semester long experiment was to determine an unknown organic acid. An organic acid is an organic compound with acidic properties. A base reacts with acids to form salts. Titrations are used to determine the concentration of unknown substances. The purpose of the KHP experiment was to determine the molarity of NaOH. HCl titrations are mainly to check technique and used to verify the molarity of NaOH solution. The hypothesis is that this acid is C4H3OCOOH.
0.1 gram of my product from the second trial was weighed in a tray and was then added to a fourth test tube containing 2.0 mL of Iron (III) chloride, which was measured using a 10 mL graduated cylinder, to test for
Condensation reaction is a chemical reaction that joins two reactants to form a larger molecule with the loss of a small molecule, usually water. 1 This reaction is used as a basis for many important process in the plastic/food industry. The most common being the formation of ester, also known as esterification. When a carboxylic acid is reacted with alcohol in the presence of a dehydrating agent, ester and water molecule are formed as products:
When using different methods to measure pH levels there are some tools that can be useful. Some more than others but by putting into action the different methods it may determine which tools will work best and give the best results when testing the pH within a solution. The pH, which stands for the proportion of hydrogen ions in a solution, could be acidic (acidosis), neutral or basic (alkaline). The pH scale goes from numbers 1 through 14. A pH of 7 is neutral;
Procedure: Filled each test tube with substances provided and subjected them to various conditions. These conditions included, heat, cold water, hot water, acid and basic additions and tested on litmus paper. The reactions were observed and documented at each step.
An ester was synthesized during an organic reaction and identified by IR spectroscopy and boiling point. Acetic acid was added to 4-methyl-2-pentanol, which was catalyzed by sulfuric acid. This produced the desired ester and water. After the ester was isolated a percent yield of 55.1% was calculated from the 0.872 g of ester recovered. This quantitative error was most likely due to product getting stuck in the apparatus. The boiling point of the ester was 143° C, only one degree off from the theoretical boiling point of the ester 1,3-dimethylbutyl, 144 ° C. The values of the
Sodium hydrogen carbonate was added to the solution until it becomes neutral. Ph paper was used for this test to determine its ph value.
Purpose the purpose of this experiment was to perform test to detect the presence of carbohydrates, proteins, lipids, and nucleic acids. Explain the importance of a positive and a negative control in biochemical test. Use biochemical test to identify an unknown compound.