Read the thermometer, to the hundredths place, until the temperature is stable. Record in Table 1 below. Add rows to the table as needed. 6. Place the test tube assembly into the beaker of ice water.
When our filtered solution started to cool off over time crystals started to form. Then we used the vacuum filtration system to separate the crystals from the cold water we used to wash them. After letting our crystals dry over night in a sealed beaker we weighed them the next day to find out what percent of crystals we were able to recover. After weighing the crystals I determined we were able to recover 4.8 grams of the original 6 grams of Acetanilide for a recovery rate of 80%. Part Two: 1: The purpose of this experiment was to remove the contaminants from the impure Acetanilide and see how much of the crystals we could recover through the recrystallization process.
Then the content of the chloride in the original salt is then calculated using stoichiometry (Chemistry Department, 2014). Theory: Gravimetric analysis is the measurement of mass, which by definition is categorized into four types however the use of one is only necessary in this experiment, which is precipitation (Gravimetric Analysis, 2012). Therefore the goal is to determine the original amount of ion. This is by isolating the ion in solution by a precipitation reaction, filtering and washing the precipitate free of pollutants, then the conversion of that precipitate to a product of the unknown sample given (Gravimetric Analysis, 2012).Therefore determining the quantitative of that substance by the precipitation reaction. The equation of the precipitate proceeds as follow if followed by the criteria given.
The Solubility of Potassium Nitrate Introduction The purpose of this experiment was to observe how temperature affected the solubility of solid potassium nitrate that was put in different solvents. The temperature was not the other thing that was being varied to observe the solubility of potassium nitrate, the amount solute was also varied and the kinds of solvents in this experiment were varied. The nature of each solvent changes due to the common ion effect which is basically means that the concentration of a soluble salt is reduced if there is a common ion with that salt. Also potassium nitrate solubility in basic and acidic places was also determined, to see if it affected the temperature. The moles of KNO3 s/ Kg solvent were needed to calculate the correct molal concentration.
My hypothesis for the experiment was that the optimum temperature for catalase to function is 98.6o F because this is the optimum temperature for the human body. The optimum pH level for the catalase function is 7 because the human’s optimum pH is 7. Materials and Methods Forceps Test Tubes Raw Liver Hydrogen Peroxide Test Tube Rack Gloves Goggles Pipette Waste Beaker Beakers Hot Plate Ice Bath Thermometer The procedure that we used to do the normal catalase activity was that we first transferred 2 ml of hydrogen peroxide solution into a clean test tube. Next we took
Acid Base Titration Purpose: The purpose is to calculate the molarity of a NaOH solution by titrating the base with 5mL of standard HCl solution in each trial. By adding the base with unknown molarity to the acid with 0.10M the molarity of NaOH can be calculated. The base, NaOH, helps bring the pH of the acid, HCl, closer to seven, which neutralizes it. When using the buret the amount of NaOH used is able to be determined. Then by writing a balanced chemical equation and using the titration formula, Nb+Ma+Va=Na+MbVb , the molarity is able to be determined.
It is based on the manipulation of the solubility at various temperatures. To have an successful recrystallization of the solid, there has to be an ideal solvent meaning the liquid in which the solid or solute is infinitely insoluble at room temperature and infinitely soluble at high temperature. This experiment will determine if the Benzoic acid will truly be soluble in the polar solvent such as water. It will also show the efficiency of the recrystallization process by comparing the experimental and literature values of melting point of the pure benzoic acid. Experimental: The experiment started with measuring the melting point range of impure benzoic acid.
3. Since dealing with enzymes, it was important to choose well the different temperatures for the experiment – for example, not making all five temperatures high because then it would not take effect. Observation during the experiment After the digestion of the gelatines was completed, the silver salts on the film peace chipped off and left a clear piece of film. The silver salts that had fallen were left as a black substance that remained at the bottom of the test tube. The Effect of Temperature Increase on the Digestion rate of Gelatine by Trypsin by the time taken for the silver salts on the exposed film pieces (in trypsin solution) to fall off, leaving clear film pieces: Temperature of the 2% trypsin solution (°C) ±0.5 | Time taken for film pieces to become clear (seconds) ±0.7 – Trial 1 | Time taken for film pieces to become clear (seconds) ±0.7 – Trial 2 | 25 | 186.6 | 184.7 | 35 | 150.0
Determination of Freezing Point and Verification of Freezing Point Depression for a Mixture by Linah Richer Partners: Maike Blakely CHM317 Preformed: Nov. 8th, 2013 Report: Nov. 19th, 2013 Abstract: The purpose of this experiment is to determine the freezing point of the solvent, biphenyl, and verify the freezing point depression equation ΔTf=-ikfnsolutemsolvent. The addition of solute will lower the vapor pressure of the solvent/solute mixture resulting in the lowering of the freezing point for the mixture solution. The experiment resulted in the experimental difference in the two trial freezing points to be 0.08 K leading to a calculated change in temperature freezing to be -1.92 E -5 K, and an overall decrease in temperature freezing of the solute/solvent solution compared to the pure solvent solution. Introduction: Experimentally it is understood that the addition of a nonvolatile solute to a solvent will lower the vapor pressure, raise the boiling point and lower the freezing point. In this experiment, the freezing point for the solvent biphenyl will be determined theoretically and experimentally, as well as the verification of the freezing point depression equation for a solvent/solute mixture.
Dependent Variable: The time taken in seconds the enzyme to react at different temperatures. This is because the temperature of the enzyme is reacting at will either make the enzyme reacts faster or slower. The rate of digestion will be calculated by 1/t (sec-1) Controlled Variables: concentration of enzyme (3 ml lipase) X nextag shop; Lipase Concentrate-HP 90 UltraCaps - Integrative Therapeutics; $24 (http://www.nextag.com/enzyme-lipase/compare-html) concentration of substrate (3 ml cooking oil) concentration of inhibitor (1 ml bile salt) All of these are fixed so that it does not affect the reaction. Introduction: Proteins that are made up of long chains of amino acids are called enzymes. These enzymes act as catalysts in chemical reactions which decreases the activation required for the reaction and consequently