Introduction Research in chemistry incorporates both microscopic and macroscopic properties. Essential to the properties compounds have both molecularly and environmentally is the ions and metals that make up many compounds. The properties of these chemicals depend heavily on the atoms that make up each particular chemical. Whether the compound is monoatomic, polyatomic, or even a polymer, being able to identify a compound is an essential tool in being able to make predictions and assumptions about the properties a specific chemical may have. Take for example the research being done on phosphorous and fluorine during World War II in Germany and during the Cold War which were able to be used as weapons, or during the early 1930’s when Germany …show more content…
After conducting the solubility test the unknown compound was identified as soluble. This process eliminated calcium carbonate as an option as a chemical. Since the calcium and carbonate ions do not dissociate in water, the solid compounds remains visible; this is not in agreement with the qualitative analysis of dissolved compound. The pH test revealed that the compound was neutral. This eliminated all basic and acidic compounds. Compound not derived from a strong acid and strong base pair, such as sodium acetate, sodium carbonate, ammonium chloride, ammonium sulfate and potassium carbonate, were eliminated as options of the compound. A limitation of this experiment is that if an acid and base were both contaminating the solution a neutral reading may also appear. By using Logger Pro and a pH probe more accurate results for the pH could be taken. The halide, acetate or sulfate test indicated that a halide acetate or sulfate was in the unknown compound. This test is facilitated by the fact that all halide, a few acetate and a few sulfate containing compounds react with silver to form a silver halide, silver acetate or a silver sulfate compound. All compounds not containing a halide, acetate or sulfate (calcium nitrate and potassium nitrate) were eliminated. The sulfate ion test revealed that the compound did not contain a sulfate due to a lack of precipitate formation. This test utilizes the fact that sulfate ions react with barium …show more content…
The rate of reaction between magnesium and hydrochloric acid at room temperature was significantly slow. This process consumed a critical amount of time in lab. In order to synthesize magnesium chloride a sample of 0.254 ±0.001g of magnesium ribbon that was cut into smaller pieces was placed in a solution of hydrochloric acid that was labeled as being 6M. Unfortunately the HCl depleted and excess magnesium remained in solution after a pH test confirmed that all the HCl had been consumed in the reaction. Particles of magnesium were removed from the solution and placed into a 250mL beaker of known mass. The beaker was then weighed and the difference in weight was calculated. This value of magnesium remained was subtracted from the original amount of magnesium to calculate how much magnesium remained in solution. The solution of aqueous magnesium chloride was then heated to evaporate the remaining water and then weighed on a scale. Ultimately the percent error of 41.6% indicates that many sources of error through this process. One major source of error is that magnesium chloride is a hexahydrate, and water moisture from the air may have evaporated into the compound before weighing. Another source of error is that water droplets condensing on the side of the beaker added mass that was assumed to be only the synthesized compound. The two purity tests that were conducted, pH and flame tests, indicated that no basic or acidic compounds were
The purpose of this lab is to observe the reaction between hydrochloric acid and magnesium metal. When the substances are reacted over water, the products produced are a salt in aqueous solution and a gas. While the salt remains in the water as part of a solution, the gas produced will float to the top. Though water vapor pressure will affect the pressure of the gas in the eudiometer, it is possible to apply Dalton’s law of partial pursues to find the dry pressure of the gas. When the dry pressure is determined, the volume of the gas at STP can then be determined and what the experimental volume of one mole of the gas would be at STP.
Abstract In this experiment the separation of a copper (II) chloride and sodium chloride mixiture was attempted. The main aim was to separate the compounds from eachother while receiving as much of the original mass of both substances as possible - in perfect conditions the original mass will be received after seperation. Many techniques were considered but dissolution, filtration and evaporation proved to be easiest and most reliable in a school environment with school equipment. The copper (II) chloride and sodium chloride mixture was dissolved in a methanol solution and filtered out leaving the sodium chloride behind.
The central purpose of this experiment was to determine the experimental empirical formula of an oxide of magnesium by performing a synthesis reaction. It was hypothesized that the formula that was derived from the recorded data would be identical to the theoretical empirical formula. After performing calculations with the data that had been collected within the duration of the experiment, it was deduced that the empirical formula of the product generated by the synthesis reaction was Mg5O6. Since the calculated formula did not match the postulated formula, MgO, the inceptive hypothesis was confuted. There was a large discrepancy in the results of students who replicated this experiment, the variation in data possibly having been evoked by the dissimilarity in
The solubility rules determined whether a compound would form a precipitate or not. These rules have stated that some compounds such as acetates, nitrates, and iodides are soluble. Similarly, compounds such as carbonates, phosphates, and sulfides have been stated as insoluble. These rules helped to predict the products of the new compounds that were created. The reactions that took place were are double replacement reactions.
The purpose of this lab was to determine the percent water in magnesium sulfate heptahydrate, or Epsom salt. The experimental percent water is determined to be 42.06% in both trials, making the average also 42.06%. To determine this percent water a heating and cooling procedure was used. First, the vials were cleaned of impurities using the lab oven and were not touched after this point.
Results: Table 1: Results from the Salicylic acid (g) and the Purity of ASA (g) Experiment Mass of salicylic acid (g) 0.14 g Mass of filter paper (g) 0.47 g Mass of “impure” ASA + filter paper (g) 0.56 g Mass of prepared “impure” ASA (g)
Abstract: The purpose of this experiment was to identify given Unknown White Compound by conducting various test and learning how to use lab techniques. Tests that are used during this experiment were a flame test, ion test, pH test, and conductivity test. The results drawn from these tests confirmed the identity of the Unknown White Compound to be sodium acetate (NaC2H3O2) because there were no presence of ions and sodium has a strong persistent orange color. The compound then will be synthesized with the compounds Na2CO3 and HC2H3O2 to find percent yield.
TLC was used to identify the actual unknown product as well as other products/reactants present in the filtered solution. The procedure was conducted by placing a TLC plate in a developing chamber that is filled with a small amount of solvent. The solvent cannot be too polar because it will cause spotted compounds on the TLC plate to rise up too fast, while a very non-polar solvent will not allow the spots to move. The polarity of the spots also determines how far it moves on the plate; non-polar spots are higher than polar ones. After spots on the TLC form, the Rf values are calculated and used to analyze the similarity of the compounds.
Since lead was not present, the "Part A" test tube, which contained precipitate from the "Unknown 4" substance, was now to be tested for the presence of silver. The "Part A" test tube 's precipitate was first washed with deionized water to remove any contaminants. When 2 mL of 6M NH4OH was added, white precipitate deposited at the bottom of the test tube. After centrifuging the "Part A" test tube, the liquid was poured into a clean
Range: The data generated in precision and linearity was considered for establishment of Range. The sample weight of 1250 mg to 3750 mg was taken for analysis and it was found to be within the linearity and precise. Robustness: Reliability of the method was done about deliberate variations in method parameters like a. Variation in the flow rate of mobile phase (±0.1 ml/min) b. Variation in cooler temperature (±2 nm)
4.1 Evaluation Assumptions It was assumed that the reactants used reacted with each other completely according to their mole ratios. It was also assumed that no impurity was present in the reactants used. Another assumption was that only ascorbic acid in the bell pepper solution reacted with the triiodide ion. It was assumed that the bell pepper was completely juiced without any loss.
Therefore, there was definitely error. The ionic solids potassium chloride and sodium chloride split into two particles in solution, so their concentration should be doubled, which needs to be accounted for more accurate
Introduction: In this lab, of water in a hydrate, or a substance whose crystalline structure is bound to water molecules by weak bonds, is determined by heating up a small sample of it. By heating, the water of hydration, or bound water, is removed, leaving only what is called an anhydrous compound. Based on the percent water in the hydrate, it can be classified as one of three types: BaCl2O ⋅ 2H20, with a percent water of about 14.57%, CuSO4
The 20th century brought an explosion of new chemical products for consumers. Chemicals bring about benefits upon which modern society is entirely dependent. From 1 million tons in 1930 to several hundreds of million tons today, the global production of chemicals has a significant increase. The chemical industry continuously converts raw materials, such as oil, natural gas, air, water, metals, and minerals into thousands of different products. Chemical products are used at work or even at home every day such as cleaning chemical liquids, fertilizers, paint, and fuels.
The objective of this experiment was to learn to prepare stock solutions and determine specific gravity and density of sodium chloride of known concentrations. This lab required us to prepare a stock solution and use that stock solution for three dilutions. Each dilution had a different molarity because of the end volume. The first diluted solution had a concentration of 0.3107 M and a density of 1.0081 g/mL. Out of all the dilutions this was the lowest concentrations because it had to most water added to the stock solution. The second diluted solution had a concentration of 0.6213 M and a density of 1.0215 g/mL. The final diluted solutions had a concentration of 1.5536 M and a density of 1.0579 g/mL. This solution had the highest density and