Principles of Chemistry Lab

6-3: This process is used by cells to manufacture _biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products__

Procedure: I used a ruler, thermometer, and scale to take measurements. I used a graduated cylinder, short step pipet, scale, and ruler to determine volume and density. I used a volumetric flask, graduated pipet, pipet bulb, scale, and glass beaker to determine concentrations and densities of various dilutions.

Abstract: One mixture of two unknown liquid compounds and one mixture of two unknown solid compounds were separated, isolated, purified, and characterized by boiling point. Two liquid unknowns were separated, isolated, and purified via simple distillation. Then, the process of an acid-base extraction and washing were used to separate two unknown compounds into two crude compounds: an organic acid and a neutral organic compound. Each crude compound was purified by recrystallization, resulting in a carboxylic acid (RCO2H) and a pure organic compound (RZ). The resulting mass of the pure carboxylic acid was 1.688g with a percent recovery of 31.80%, the boiling range was 244-245 °C, and its density was 2.0879g/mL. The resulting mass of the pure organic solid was 2.4902g with a percent recovery of 46.91%, the boiling range was 52.0-53.4°C, and its density was 1.5956 g/mL.

The Identity of a chemical compound is extremely critical to observe. The identity can lead to discovering its properties and can aid in its classification. Thus scientist all around the world put high emphasis on the procedure to identify a compound through the flame test and chemical testing. Flame test works to identify the cation within the compound, while chemical testing using certain compounds and acid identifies the anion.

The proof (twice the % alcohol) starts at its maximum and goes down (as the alcohol evaporates). If we start with a high concentration of alcohol, we will get the azeotrope (95% alcohol, 5% water) for a while, then the concentration will decrease.

3.6.1. BAP (Benzyl amino purine) stock solution (2mg/ml): 20mg of BAP being weighed and dissolved completely in 1N NaOH to a final total volume of 10 ml with autoclaved double distilled water to obtain a stock concentration of 2mg/ml was prepared and stored in clean autoclaved vials at -4°C.

Identifying this organic acid was an extensive task that involved several different experiments. Firstly, the melting point had to be determined. Since melting point can be determined to an almost exact degree, finding a close melting point of the specific unknown can accurately point to the identification of the acid. In this case the best melting point

This lab dealt with determining the percentage Acetic Acid (CH3COOH) in Vinegar. The main purpose of the experiment was to make sure if the vinegar solution has the right amount of acetic acid, which is about 5%, using the titration technique. The hypothesis is that the percentage of acetic acid in the vinegar solution used will be very close to the usual percentage of 5%. The experiment was to use the standard solution of NaOH to titrate the given vinegar solution to determine the percent concentration of acetic acid. The result of the experiment came out to close the 5% of the normal percentage of acetic acid contained in a vinegar solution, but was inaccurate due to two errors in the experiment.

The first question was which of the samples would float on top of water? The answer is oil because it is less dense than water. Ethanol and 2-propanol don’t float because they have a greater density than water. The second question is if you wanted to make layers for the four liquids in a graduated cylinder, in what order would you pour the liquids into the cylinder? The answer is 2-proponal, ethanol, oil, and water.

The purpose of the Acid-Base Titration Lab was to determine the concentration of sodium hydroxide by titration against a standard solution. A titration is a laboratory method used to determine the concentration of an acid or a base in a solution by performing a neutralization reaction with a standard solution. It detects the equivalence point between the acid and base where they neutralize each other. The materials used in this procedure were HCL solution, water, ring stand, burette, burette clamp, unknown concentration of NaOH, phenolphthalein, erlenmeyer flask, and graduated cylinder.

Second, the plunger of the titrator was depressed. Third, the titrator was inserted into the plug in the top of the Sodium Thiosulfate titrating solution. Fourth, the bottle was inverted and the plunger was slowly withdrawn until the large ring on the plunger is opposite the zero line on the scale. If a small bubble appeared in the the titrator barrel, it was expelled by partially filling the barrel and pumping the titration solution back into the reagent container. This was repeated until the bubble disappeared. Fifth, the bottle was turned upright, and the titrator was removed. Sixth, the tip of the titrator was inserted into the opening of the titration cap. Seven, the plunger was slowly depressed to dispense the titrating solution until the yellow-brown color changed to a very pale yellow. The tube was gently swirled during the titration to mix the contents. Eight, the titrator and cap was carefully removed, while the titrator plunger was not disturbed. Nine, eight drops of Starch Indicator Solution was added. The sample had turned blue. Ten, the titration tube was capped. The tip of the titrator was inserted into the opening of the titration tube cap. Eleven, the titration was continued until the blue color disappeared and the solution became colorless. Twelve, the test result was read directly from the scale where the large ring on

This value, like in Part A, was discovered to be one, resulting in the same number of moles of NaOH and HCl. This mole value was then divided by the total volume of HCl solution which was 5 mL. This calculation needed further conversion from moles/mL through the multiplication of 1000 mL resulting in unites of moles/L . The final concentration obtained for Run 1 was about 1.2707858 M and 1.2786574 M for Run 2. The average, or final, concentration value obtained was then about 1.2747216

After a harsh Wednesday due to Chemistry Lab and Organic Chemistry, I enjoy sitting in the patio area of Cafe 1919 and enjoy a Panini along with a Caprese salad. Both the main dish and side contain a fruit I once hated as a child. Tomato have always been the part of the burger I threw out, the part of the salad I did not touch, the part I could never swallow. Even throughout high school, I always hated tomatoes, but ever since I got to UCLA my love for this fruit exponentially grew out of nowhere. One day as I was enjoying my usual Wednesday lunch, I wonder what gave these little morsels such a juicy taste. Perhaps UCLA does but the best fruit and vegetables for their students, perhaps the oil the tomatoes bathe in give it its rich taste, or perhaps we have those hidden GMO, gentically modified organisms, that people argue over its stability. I search if there is any known gentically altered tomatoes and the search engine directed me to links that talk about a product known as the Flavr Savr. Interesting enough the product known as the Flavr Savr, which is a gentically altered tomato is actually the first FDA approved GMO to hit to the market. After discovering the first ever GMO my curious mind started asking questions that I needed to know. I wonder what exactly is the Flavr Sav? When was it created? Who created it and how? Was there a reason they chose to mess with the DNA of a tomato? How did people response to the first of many gentically altered food? Is the Flavr

Throughout this lab, many different experiments were tested on the unknown white compound. The first test ran was the Solubility Test, which was started by measuring 0.03g of the unknown substance. Next, measure out 60ml of distilled H2O and mix with 0.03g of unknown. Use a stirring rod to the substances were mixed together, and observations were made to see if the unknown dissolves. The use of a ionic solubility chart was helpful when running this test.

At the end point in titration, stoichiometry between both the solutions lie in a 1 : 1 ratio.