Theory: The goal of the lab was to separate a neutral compound and an acid from an unknown mixture. The DCM (Dichloromethane) was added to create the organic layer. Both the neutral compound and acid were insoluble in water so aqueous NaOH was added. The acid would be deprotonated into an ion, which is soluble in water. Using the separatory funnel, the organic layer was separated from the aqueous layer. HCl was added so that the ion would protonate back into the acid and precipitate out of solution. Vacuum filtration via Buchner funnel was used to separate the acid (crystals) from the salt, NaCl. Na2SO4 was the drying agent used to remove any residual water from the organic layer. Gravity filtration helped separate the drying agent from the organic layer containing the neutral compound. The organic layer (DCM solvent) was boiled in order to separate the solvent from the neutral compound, which was in the form of crystals. Ethanol was heated up and added to the crystals of the neutral molecule which allowed the removal of impurities. The solution was placed in a hot water bath and the crystals of the neutral molecule precipitated out. The cool temperature helped crystallize the neutral compound into crystals. Finally, the neutral compound crystals were separated via vacuum filtration using a Buchner funnel. The acid and neutral compound and massed via an analytical balance so that the percent recovery can be calculated. Melting point (Mel-temp) was used to determine the
6-3: This process is used by cells to manufacture _biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products__
The main objective of this experiment is to differentiate between a physical change and a chemical change.
This experiment combined all the knowledge of the previous labs performed throughout the semester. An unknown mixture containing an organic acid or base and an organic neutral compound in nearly equal amounts needs to be separated to its separate components. An understanding of solubility, extraction, crystallization and vacuum filtration is necessary in order to
A chemical reaction is when substances (reactants) change into other substances (products). The five general types of chemical reactions are synthesis (also known as direct combination), decomposition, single replacement (also known as single displacement), double replacement (also known as double displacement), and combustion. In this lab, the five general types of chemical reactions were conducted and observations were taken before, during, and after the reaction. Then the reactants and observations were used to determine the products to form a balanced chemical equation. The purpose of this lab was to learn and answer the question: How can observations be used to determine the identity of substances produced in a chemical reaction?
Examine a piece of nichrome wire. On the data sheet, record the color and the luster of the metal. Use a forceps to hold the wire in the flame of your burner for about two minutes (recall where the hottest part of the flame is located). Describe the appearance of the wire while held in the hottest part of the flame. Allow the wire to cool and reexamine it. From your observations, determine if there was a physical or a chemical change. Give specific reasons for your conclusions. Save the nichrome wire for step #2.
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.
| Can see particles of both. When mixed with water salt dissolves and sand is left.After filter sand is left and salt-water goes through.After evaporations of salt-water, salt is only left in dish.
Day 1. Michael was coming home for vacation from college. When he got home he found out that
Substances A and B have an appearance of a white solid like. Substances A and B were put into a test tube and on the Bunsen burner. As a result, B melted faster than A. A was slow to melt. The reason why B melted faster than A is because it has a lower boiling point than substance A which made it melt faster. It also shows that A needs more energy than B to be broken down.
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.
5. Zoom Out by clicking on the green arrow next to the Save button. Click on the Stockroom and then on the Clipboard and select Balloon Experiment N2. Again, set the temperature, pressure, and moles to 298 K, 1.00 atm, and 0.300 moles, respectively. You may have to click on the Units button to change some of the variables to the correct units. Repeat the experiment with this gas labeling the data link ‘Real Gas N2.’
Purpose: The purpose of this experiment is to observe a variety of chemical reactions and to identify patterns in the conversion of reactants into products.
In this experiment, a mixture of unknown #3 was used. That mixture had acid, base, and neutral. We added solvent to the unknown. It is important to know the density of the solvent in order to determine which is the aqueous layer and which is the organic layer. If the solvent that has more density than water, so the organic layer will be the lower layer, while if the solvent has lower density than water, the organic layer will be the upper layer. This will make an error if the determination of the layers was wrong after added the strong acid or the strong base. We added 5% HCl to the mixture in order to separate the base in the aqueous layer and form its salt. Same thing, we add 5% NaOH to the mixture in order to separate the acid and form its salt. In order to recover the base, we add 10% NaOH to the HCl extraction. The result will be salt with a base. Same thing for the acid, in order to recovered it, we added 10% HCl. The reaction will give us salt with an acid. For the neutral, we added sodium sulfate as a drying reagent in order to dry water and separate the neutral part as pure.
The luminous yellow flame is smoky because no air is entering the burner and hydrocarbon is converted into carbon dioxide
Dispense .5 mL water into the already weighed conical vial, replace cap and face insert on its down side.