Untitled Quiz

Chemical Experiments - First Semester

• Chemical Equations: Various chemical reactions were studied and documented, including those involving carboxylic acids, salicylic acid, and other compounds. Specific formulas and products were noted for each reaction.

Carboxylic Acid Properties

• Solubility: Solubility in water decreases as the number of carbon atoms in the carboxylic acid chain increases. Stearic acid (18 carbons) is less soluble than acetic acid (2 carbons) or benzoic acid (7 carbons).

Oxidation of Carboxylic Acids

• Potassium Permanganate: Using potassium permanganate (KMnO4), experiments were conducted to observe the oxidation of various carboxylic acids (acetic, formic, benzoic, and oxalic). The results revealed the formation of manganese (IV) oxide (MnO2) which is a reddish-brown precipitate in some cases.

Salicylic Acid Reactions

• Ferric Chloride: Reactions between salicylic acid and ferric chloride produced ferric salicylate as a product, and this was indicated by changes in color in the reaction mixtures.
• Bromine Water: Reactions with bromine water of salicylic acid produce specific precipitates
• Millon's Reagent: Reactions with Millon's reagent resulted in mercuric salicylate precipitates, appearing in a reddish/pink color.
• Soda-Lime: Salicylic acid reacted with soda-lime (NaOH/CaO) under heat, resulting in a glue/paste-like odor.
• Ester Formation: Salicylic acid reacted with methanol and concentrated sulfuric acid, producing methyl salicylate (a process called ester formation) resulting in the minty odor of oil of wintergreen

Preparation of Aspirin

• Experiment 13: This experiment details the procedure for synthesizing aspirin from salicylic acid.
• Materials: Salicylic acid, acetic anhydride, concentrated sulfuric acid, ice.
• Yield: 100% yield was 92.31%. A detailed procedure and observed phenomena were documented.

Properties of Acetamide and Urea

• Experiment 14: Acetamide and urea were examined in various tests, and their properties were noted.

Reactions of Acetamide

• Base-Catalyzed Hydrolysis: Acetamide, when reacted with sodium hydroxide, produced ammonia and sodium acetate.
• Acid-Catalyzed Hydrolysis: Acetamide reacted with a mixture of sodium nitrate, sulfuric acid to produce acetic acid and nitrogen gas

Aniline Reactions

• Basicity: Aniline reacted with water to a very small extent. It was tested with litmus paper, and observed to be a weak base.
• Salt Formation: Reactions with ferric chloride produced a salt-like solid, and the experiment noted changes in color.
• Bromine Water: Addition of bromine water to aniline resulted to produce insoluble globules.
• Diazotization: Aniline underwent diazotization—a reaction involving the process of conversion of aniline to its diazonium salt.
• Formation of Dyes: This experiment explored the formation of dyes from aniline.

Formation of Phenol

• Diazotization, then Decomposition: Phenol was produced by reaction with diazotized aniline. The result was the presence of a paste-like odor and reddish/pink chemical color. This experiment also observed the behavior and resulting odor of the mixture.