Synthesis Of Alum Lab Report

After each of the solids were completely dry, each was placed into a MelTemp device. The temperature at which each solid began to melt and completed melting was recorded.

20 ul of DNA was added to 20ul of Master Mix. The Master Mix contained primers, dNTPs, Mg2+, Taq DNA polymerase, and yellow dye. Both the DNA and Master Mix were mixed with the micropipette. The DNA was then put into the thermal cycler containing 40 cycles of PCR amplification, amounting to 3.5 hours of amplification.

The vial was removed from the heat and cooled to room temperature. The spin vane was rinsed with 2-3 drops of warm water over the conical vial. The vial was cooled to room temperature then placed in an ice bath for 15 minutes. The liquid was decanted from the mixture and the resulting crystals were dried on filter paper. The crystals were then placed on a watch glass for further drying. The crystals were weighed and a small sample was placed into a capillary tube for melting point determination.

This lab could have contained errors. The errors could have happened when performing the lab. Some of the possible errors in this lab are:

Purpose: The purpose of this lab is to further observe four types of chemical reactions. This lab will show four types of distinct chemical reactions and will increase my knowledge on each type.

6) Transfer the crystals (quantitatively) from Step 4 to the funnel. Use about 5 mL of distilled water to rinse any solid that remains in the beaker onto the filter paper. Let the solid air-dry with the aspirator running for a few minutes.

melting point of an unknown substance to that of a true compound. This method can be

Then 20mL of 6.0M sulfuric acid was carefully added to the reaction beaker while being stirred with a stir rod. A stir bar was inserted into the reaction and the beaker was put on top of a hot plate to dissolve the solids that formed. After the solids were dissolved, the reaction was filtered with a vacuum filter as done previously. The reaction beaker was cooled in an ice bath created by adding ice chips and water to a larger beaker for the alum crystals to precipitate. The inside of the beaker was scratched with a stirring rod to facilitate the formation of crystals. The vacuum filter was set up

sterilized the loop by heat and tube streaked 26A and 26B on the agar and then incubated at 37

Chemical change can be defined as a change that occurs at the molecular level, which includes making or breaking between atoms to produce new chemical substances. Signs that can indicate a chemical change are a difference in colour, change in heat temperature, gases being produced or precipitate forming. Chemical changes are categorised into 5 types of reactions; combination, decomposition, single-displacement, double-replacement and combustion.

The purpose of this lab was to investigate the method of extraction as a means of isolating pure compounds. In this experiment, the acid-base extraction method was used on a mixture composed of three separate components: an acid, a base, and a neutral component. The extraction solvent used was diethyl ether. Through sequential acid-base reactions where aqueous 10% NaOH and aqueous 10% HCl were used in a separatory funnel, the three components were extracted, isolated and then recovered through precipitate reverse reactions using 10% NaOH and concentrated HCl. Once the components were isolated and recovered, a melting point analysis was performed and these values were then compared to the values in the laboratory handout in order to identify the compounds. Percent yield of each compound was also calculated. It was found that the mixture contained Benzoic Acid with a melting range of 121.6-122.9 oC and a percent yield of 292%, Meta-nitraniline with a melting range of 111.4-112.2 oC and a percent yield of 204%, and Biphenyl with a melting range of 70.6-73.5 oC with a percent yield of 128%.

As you are allowed to attend only one lab make-up session, please contact Prof. Jennifer Chabra for further details. Please also copy me on the

The hypothesis that as the level from which the electron jumps is increase, the emitted frequency would also increase, was supported in this lab. As the level of the electron was increased, the emitted frequency increased in a manner that was indirectly linear to the of the level of the electron. The accuracy in this lab was excellent with a 2% and 1% error for the hydrogen gas portion. The accuracy for the measurement of the measure of the wavelengths of two colors in the helium gas was also excellent with percent errors of 2.7% and 2.9%. A potential systematic error in this lab could have been incorrectly measuring the distance from the diffraction grating to the gas tube. This would cause every calculated wavelength to either be larger

Alum is a chemical compound that can be created by oxidation and a precipitate. Oxidation is a process in which electrons are lost and oxygen combines with another element, resulting in a change of appearance. All types of alum are double salts but not all are used in a crystal form. Certain types of alum are used in baking, medicine, or pickling. The alum created in this lab became a crystal in an octahedral form. The purpose of this lab was to create alum crystals from aluminum foil and various solutions. Aluminum is a common metal and by adding an aqueous solution to small pieces of aluminum, a crystal structure can be formed. Aluminum is being reduced in the reaction contributing to the formation of the octahedral alum crystal. Hydrogen was being oxidized in the reaction as well. The purpose of the experiment was to take aluminum foil and transform it into an alum crystal through oxidation, in order to calculate the amount of alum created.

Brittain, C. G. (2009). Using Melting Point to Determine Purity of Crystalline Solids. Retrieved from http://www.chm.uri.edu/mmcgregor/chm228/use_of_melting_point_apparatus.pdf