Silver Nitrate Test Lab Report

Experiment 55 consists of devising a separation and purification scheme for a three component mixture. The overall objective is to isolate in pure form two of the three compounds. This was done using extraction, solubility, crystallization and vacuum filtration. The experiment was carried out two times, both of which were successful.

The mole is a convenient unit for analyzing chemical reactions. Avogadro’s number is equal to the mole. The mass of a mole of any compound or element is the mass in grams that corresponds to the molecular formula, also known as the atomic mass. In this experiment, you will observe the reaction of iron nails with a solution of copper (II) chloride and determine the number of moles involved in the reaction. You will determine the number of moles of copper produced in the reaction of iron and copper (II) chloride, determine the number of moles of iron used up in the reaction of iron and copper (II) chloride, determine the ratio of moles of iron to moles of copper, and determine the number of atoms and formula units involved in

3. When the anhydrous sample was rehydrated, only 93.4% of the sample could be recovered. This was because some of the mass of the sample remained stuck to the filter paper and could not be measured in the final mass calculation. This automatically resulted in less mass and did not allow for 100% of the mass to be recovered.

After about 1 minute of shaking, the two layers separated. The organic layer on the top layer (consisted of ethyl acetate and naphthalene) collected for further experiment; by adding Sodium Sulfate into organic phase and filtering the Na2So4 from the solution using the wool. The dried organic layer was weighed to get its mass and the residue of Na2SO4 were rinsed with ethyl acetate under vacuum (rotary evaporator). The acid extract on the bottom layer which is a combination of benzoic acid and NaOH were collected in the 50 mL Erlenmeyer beaker for the recovery of acid.

The purpose of the lab copper- silver nitrate reaction is to find the mole relationships between reactants and products. My hypothesis was that the mole relationship between silver and copper will be 2 mol Cu: 1 mol Ag ratio. My hypothesis is supported by the data I found during the lab. First evidence, in the beginning of my calculation I have to determine the mass of copper that reacted during the experiment and converted to moles of copper and got .0033 moles of Cu. Next, I determined the mass of silver produced during the experiment and converted into moles of silver and got .0063 moles of Ag. After I found the moles of copper and silver, I determined the value of the ratio of .0063 moles Ag /.0033 moles Cu and got 1.90 moles. 1.90 mol

Possible reasoning for a lower yield could be loss of product during separation process, particularly leaving some product behind in Erlenmeyer flask. Another possible explanation could be the wash of product with not enough cold water, which increases the solubility of the product, thus lowering the yield. Also the product was lost during purification process, recrystallization. Solid could be dissolved below the boiling point of the solution, thus required more solvent, resulting in a lower

1. Suggest at least one chemical reason why your percent yield is less than 100%. (Incomplete reactions? Side reactions? Stability of reagents?)

Purpose of this experiment was to find the amount and percent of water in a hydrated salt. Also, to successfully determine percent error and standard deviation. Hydrated salts are substances that occur naturally who usually contain an amount of water molecules chemically bonded to the compound. A few hydrated salts have weak bonds within the water molecules which allows heat to remove the water molecules creating an anhydrous salt. Hydrated salts that lose water molecules to the atmosphere without a heat source are known as efflorescent. Salts that readily absorb water are called deliquescent. An example of an anhydrous salt would be Magnesium Sulfate or also known as Epsom Salt. Epsom salt separates under heating and becomes

Silvershell Beach is the home to many different aquatic species and other forms of wildlife. Last lab block the class and I went into the ocean at Silvershell beach and took seven different seine net samples. With each sample we took, we noticed a variety of different organisms. As we moved around different areas of the ocean, we would come out with changing species and number of species that we did not find in other areas of the water. Species we found included sea robin, hermit crabs, moon jellies, minnows, shrimp, eels, and more. Sample one and two were taken from around the same area in the water and there was a reappearance of three of the species. In sample one we found hermit crabs, minnows, moon jellies, and a sea robin. In sample two

Strontium nitrate, the limiting reagent, was poured into the copper(II) sulphate solution, the excess reagent, rather than the other way around. This is a minor systemic error, because even if some of the strontium nitrate remained in its initial beaker, the beaker was thoroughly rinsed out multiple times. The error causes the final mass of the filter paper and precipitate to be slightly decreased, as not all of strontium nitrate reacts with the copper(II) sulfate. This can explain why the percent yield in 92.2%.

The purpose of this experiment is to distinguish the relationships between reactants and products, in addition to expanding on concepts such as single displacement reactions, mole ratio values, moles to mass, theoretical yields, limiting reactants, excess, stoichiometric relationships and percentage errors.

After putting the CH2Cl2 to a beaker containing the drying agent anhydrous sodium sulfate, a sticky white solid was recovered.

The reaction took place in a conical vial and .2mL of each of the reactant samples were added to it along with some 95% ethanol. Two drops of NaOH were added shortly after and stirred at room temperature for fifteen minutes. The vial was cooled in and ice bath and crystallized. Vacuum filtration was performed to filter the crude product. The crude product was recrystallized using methanol and filtered again. We made one change to the procedure and instead of using .7mL of ethanol we

Intermolecular forces hold molecules together when they are in solid or liquid state. However, water has the ability to dissociate many salts and ionic compounds. This is called dissolving. When NaCl is added to water, it dissociates into the ions; Na+ and Cl- . The positive sodium ions are surrounded by the slightly negatively charged part of water molecules (i.e. oxygen) in the water molecules and the negative chlorine ions are surrounded by the slightly positively charged part of water molecules (i.e. the hydrogen). The kinetic energy of the sodium chloride molecules increase with temperature. This destabilizes the solid state that it is currently in. This increased motion means that the molecules are less able to hold together and as such they dissolve at faster rates and larger amounts.

Once cooled, the mixture was then transferred to a separatory funnel using the funnel while avoiding adding the boiling chip. 10 ml of water was then added to the mixture. The mixture was gently shaken and the phases were allowed to separate. The funnel was then unstopped and the lower aqueous phase was drained into a beaker. 5 ml of 5% aqueous NaHCO3 was added and then shaken gently. A great deal of caution was taken into consideration because of the production of carbon dioxide gas which caused pressure to develop inside the funnel. The pressure needed to be released so the funnel was vented frequently. The phases were allowed to separate and the lower aqueous phases was drained into the beaker. After draining, 5 ml of saturated NaCl was added to the funnel and then shaken gently. Once again, the phases were allowed to separate and the lower aqueous phase was drained into a beaker. An ester product was produced and was transferred into a 25 ml Erlenmeyer flask. This organic product was then dried over anhydrous Na2SO4 to trap small amounts of water in its crystal lattices thus removing it from the product. Finally the ester was decanted, so that the drying agent was excluded from the final product.