Heats of Solution and Reaction Name: Cindy Hernandez Purpose: The purpose of this experiment is to decided if the chemical reactions are exothermic and endothermic. By finding the differences between each temperature. Overview: For this lab, we had three different chemicals involved NH4Cl, H2SO4, and NaOH. What we did with these chemicals was that we added water, except NaOH we added HCl, was that we combined both mixtures to determine if there was a temperature change. The reason why we're determining if their was a chemical reaction is to identify if it is exothermic or endothermic.
In our lab we use a more sophisticated one which included a lid on the cup with an inserted thermometer and a stirrer. Thermochemistry is the study of the heat released or absorbed as a result of chemical reactions. The measurement of the total energy of a thermodynamic reaction is called enthalpy (q). This is the basis for Hess’s law which states that if two reactions are combined to yield a third reaction, the sum of the first two is equal to the third. The energy change is the same whether the process occurs in one step or many.
Dr Khounsary explains an experiment using a fixed voltage and varying the temperature of the wire using a torch. The article further explains that the temperature coefficient of copper at 20 degrees C is .00393 and that a single degree of temperature change would increase the resistance of the wire by that amount. In the article regarding the Effect of Temperature on Conductivity (The Nuffield Foundation, 2006) the article describes how the conductivity of a wire decreases as it is heated. It provides an example schematic diagram for the test circuit and the use of Eureka wire instead of copper wire. A2a.
Pour the contents of one of the test tubes into the other and a reaction should occur and you should see a white precipitate of barium sulfate form. Then, centrifuge it for 1 minute. On the side, weight a boiling test tube containing 2 boiling chips. When the separation is complete, remove the small test tubes from the centrifuge and decant the supernatant into the boiling test tube. Add 1 mL of deionized water to the small test tube containing the precipitate and mix it and centrifuge it for 60 seconds.
Lab 4: Determination of Percent by Mass of the Composition in a Mixture by Gravimetric Analysis Introduction Thermal gravimetric analysis is used to determine the percent by mass is used to determine the percent by mass of a component in a mixture. When a mixture is heated to an appropriately high temperature, one component in the mixture decomposes to form a gaseous compound. The mass of this particular component is related to the mass of the gaseous compound. In this experiment, the percent by mass of sodium hydrogen carbonate (NaHCO3) and potassium chloride (KCl) in a mixture will be determined. Experimental First, we weighed 2 samples, each has 1 gram of NaHCO3-KCl mixture Second, we put the samples in 2 crucibles (A and B) and weighed them.
Materials and equipment: MATERIALS Labquest 20 mL syringe Labquest App two 125 mL Erlenmeyer flasks Vernier Gas Pressure Sensor ethanol, CH3CH2OH Temperature Probe 400 mL beaker rubber stopper assembly 1 liter beaker plastic tubing with two connectors hot plate Procedure: The apparatus was set up as requested by the Lab quest 34 handout and an initial pressure reading of 101.6kpa was obtained at room temperature, 22.4° C. Then the Erlenmeyer flask and the sensors were conditioned to the water bath by holding the flask down into the water bath to the bottom of the white stopper for 30 seconds, and then the valve on the white stopper was closed to keep the ethanol vapor from leaving the container at any time during the experiment. 3 mL ethanol was then introduced into the empty dry flask that was inside the water bath and the flask with the ethanol was rotated in
Ideal Gas Behavior Instructor: Nieves Montano Chem 151, Section 002G Date Work Performed: February 12, 2014 Date Report Submitted: February 20, 2014 Abstract: This paper reports a lab experiment done on the ideal gas law to determine differences in gas based upon their “R” constant difference to 0.082057. A total of seven gases were tested, which included, Ethanol, Hexane, Cyclohexane, Pentane, Ethyl Acetate, Butane and Acetone. These gases were each heated and then condensed to liquid gas to find specific values and determined Ethanol as the gas closest to ideal behavior in this experiment. Introduction: The Ideal Gas Law demonstrates the relationship of the properties of gases. This relationship is specific to the gases that are considered “ideal”.
pyridinium hydrobromide perbromide type of stationary phase column length column temperature rate flow of the carrier gas List the 4 general factors that affect the separation obtained on a gas chromatograph What specific technique is used to collect/isolate your purified unknown compound at the end of the recrystallization experiment? suction filtration 14 of 22 4/16/12 9:15 PM StudyBlue Flashcard Printing of Lab Final 2211L UGA
CHEMISTRY Name _____________________________ Lab - Molar Volume of a gas lAB 12 OBJECTIVE OF THE LAB: The purpose of this lab is to determine the molar volume of a sample of Hydrogen gas that is created through the reaction of Magnesium and Hydrochloric Acid. The concept of molar volume is that 1 mole of a gas occupies 22.4 liters at STP. Unfortunately the conditions of the lab are not at STP. You will have to use gas law formulas to calculate the volume that one mole of this gas would occupy at STP. In addition, since this lab is being done over water, and water will evaporate at any temperature, the vapor pressure of water must be determined.
No details of how the oxides of nitrogen are formed are required, other than the fact that they are formed at high temperatures. Solid particles may contain soot (carbon) and unburnt fuels. b) The combustion of hydrocarbon fuels releases energy. During combustion the carbon and hydrogen in the fuels are oxidised. 18 GCSE Chemistry for teaching from September 2011 onwards (version 1.0) Additional