This model could not be altered to include each of these processes because it would require additional items like soil, plants, and a larger jar. 3. How would the “weather” be affected if the water was at a decreased temperature? How would the “weather” be affected if the water temperature were increased? Answer = The weather would be calm in decreased temperatures because you don’t see condensation or evaporation happening when the temperature is cooler.
Laundry detergent hypothesis accept/reject = Reject// Laundry detergent also changed the viscosity of the water. What affects did each of the contaminants have on the water in the experiment? Which contaminant seemed to have the most potent effect on the water? Answer = From what I observed, oil is saturated into the soil leaving little to none of the water to pass through. While the vinegar passed through the soil leaving more dirty water.
The final crude product yield was 0.91g and the pure product yield was 0.36g. Error may have occurred during the extraction phase. Although I extracted twice with Sodium Chloride, if waste was not completely removed, it would affect the purity of the product. The distillation process may have also affected the pure product. The lab manual recommended that 0.5mL of waste be removed during distillation; otherwise it would affect the purity of the product.
The salts will be dissolved in distilled water by small quantities until the reaction reaches When ionic compounds dissolve in water, they either absorb energy from or release energy to the surroundings. If a chemical reaction absorbs heat from the surroundings, it is an endothermic reaction. If a solution releases heat to its surroundings, it is an exothermic reaction. The enthalpy of dissolution is the enthalpy change associated with the dissolution of a substance in a solvent at a constant pressure. The change in enthalpy relies on the concentration of the salt solution, because different concentrations will produce different enthalpies.
Of course the saturated solutions take time this experiment is done in a two day lab setting part one should be completed during the first day and ready for use on day two. Remember because Le Châtelier’s principle if you don’t filter the solution will rise. The removal of OH- from the UN filtered solution will cause more Ca(OH)2 to be dissolved for the equilibrium to restore. The second part of this lab takes knowledge from past experiments done in this laboratory. Using the Primary method used to standardize the concentration of HCl, this will bring much lower percent error in the Ksp For this standardization sodium carbonate should be used for determining the amount of hydroxide in the solution.
Chapter Two: Freezing Point Depression Measurements Purpose: The purpose of this lab is to measure freezing points and freezing point depression for several solutions. The freezing point depression constant (Kf) for p-xylene was calculated from freezing point measurements and used to estimate the molar masses of three unknown solutes in a p-xylene solution. The end goal of this lab experiment is to correctly identify these three unknown solutes. The molar mass of a solute is able to be determined through freezing point depression measurements because the increase in solutes disrupts crystal formation, requiring a lower temperature to form a lattice. This colligative property is important in many industries, but is clear to see when using ordinary salt to remove ice from steps or a driveway.
The indicator Phenolphthalein was the substance used to signal when the titration reached the point at which the reactants are stoichiometrically equal as defined by the balance reaction equation. Phenolphthalein is a chemical compound with the formula C₂₀H₁₄O₄ and is often written as "HIn" or "phph" in shorthand notation. Often used in titrations, it turns colorless in acidic solutions and pink in basic solutions. Sodium hydroxide or Hydrochloric acid would not have been as effective or accurate because they would have reacted with the water vapor from the air. In this lab setup, graduated cylinders or beakers were not used.
The solution added reacted by turning the solution into a transparent liquid. This reaction is endothermic because the solution HC1 and Na2EDTA added decreased the reaction as the equilibriums both shifted to the left. When Na2SO4 was added the equilibrium should have shifted to the left. The solution reacted by creating more HSO4 even more when the 10 drops of the sodium sulfate solution was added as the color changed to a much lighter solution. When NaHSO4 was added the equilibrium should have shifted to the
6. Addition of DNS at the end of the incubation period stopped the reaction by denaturing sucrase. Explain why it is important to denature sucrase before measuring product concentration. RESULTS See Table 1: Effect of pH on Sucrase Activity See Graph, Effect of pH on Sucrase Activity 1. State the optimum pH for sucrase activity and describe how sucrase activity changes at more acidic and more alkaline pH values.
When pH is high which means more OH⁻, then aluminum ions will react with hydroxide ions to form aluminum hydroxide. Phosphate ions are acting as a natural buffer. If the equipment is not washed with acid, it would cause an error. This is because the phosphorus analyzing is dealing with low concentration of phosphorus and it is easily contaminated by detergent and other chemicals and it has to be washed by using an acid and also it has to be rinsed with distilled water once it is rinsed with acid. Also refer to section 4 (discussion).