Overall reaction of the acid-catalyzed dehydration of 2-methylcyclohexanol Figure 2. Reactions for the unsaturation tests Table of Reactants and Products: Table 1. Molecular weight, density, melting point, and boiling point for all reagents used in Experiment #7 – Dehydration of 2-Methylclyclohexanol, Tests for Unsaturation, and Gas Chromatography. Name: | MW (g/mol): | Density (g/mL): | MP (C): | BP (C): | MSDS: | 2-methylcyclohexanol | 114.19 | 0.93 | -38.00 | 165-168 | Irritant, flammable | 95% phosphoric acid | 97.994 | 1.69 | 42.35 | 158 | Corrosive, irritant | 1-methylcyclohexene | 96.17 | 0.81 | -120.4 | 110 | Irritant, flammable | 3-methylcyclohexene | 96.17 | 0.81 | -124.00 | 104 | Irritant, flammable | Procedure: Part One – Dehydration of 2-methylcyclohexanol A microdistillation apparatus was assembled by securing a microdistillation flask to a ring stand and submerging it in an empty heating mantle. A thermometer and Teflon adaptor were tightly sealed into the top of the flask with the thermometer bulb being below the side arm.
The change in enthalpy relies on the concentration of the salt solution, because different concentrations will produce different enthalpies. There is an equation to determine how much of this heat energy is lost or gained when a reaction is performed. Q = c m (T1-T2) Where: q is the energy in Joules C is the heat capacity, measured in joules per gram per degree Celsius M is the mass of the solution, measured in grams J is the joules G is the grams of water T is the temperature ΔH=ΔE + PΔV = (q p +w) – w = q p Procedure: 1. Follow instructions 1-9 in Appendix A-1 to initialize the MeasureNet workstation. a.
Simple and Fractional Distillation of Cyclohexane and Toluene Purpose: The purpose of this experiment was to become familiar with the processes of simple and fractional distillation. In this experiment a mixture of two volatile compounds, cyclohexane and toluene, were separated with the process of distillation. Distillation relies on each compound having distinct and separate boiling points. The pure products were analyzed with gas chromatography to determine the success of the distillation. Introduction: Distillation is the process of heating a liquid until it boils, then condensing and collecting the resulting hot vapors.
A. ethanoic acid B. ethyl ethanoate C. hexane D. hex-1-ene 8. A compound boils at –33oC. It also dissolves in water to give an alkaline solution. Which type of bonding is present within the compound? A. metallic B. covalent (polar) C. ionic D. covalent (non-polar) 9.
Lesson 13.6 Changes of physical state: * necessary to draw a temperature-energy graph to see the change in temperature with a constant application of heat Heat of fusion - the amount of heat required to melt 1.00 g of substance. substance changing from a solid to a liquid. Heat of vaporization - the amount of heat required to vaporize 1.00 g of a substance. substance changing from a liquid to a gas. heats of vaporization and condensation are equal.
Liquids and Solids Purpose: The goal of this experiment is to be able to identify melting/boiling points of substances. We can then use these methods to identify unknown substances because of constants in melting/boiling points. Procedure: 1. Boiling Point a. Begin by adding 1 mL of rubbing alcohol to test tube and attach a thermometer to it.
Computer Additivity of Heats of Reaction: Hess’s Law 18 (1) Solid sodium hydroxide dissolves in water to form an aqueous solution of ions. (2) Solid sodium hydroxide reacts with aqueous hydrochloric acid to form water and an aqueous solution of sodium chloride. NaOH(s) + H+(aq) ) + Cl–(aq) → H2O(l) + Na+(aq) + Cl–(aq) ∆H2 = ? OBJECTIVES • • • • In this experiment, you will Combine equations for two reactions to obtain the equation for a third reaction. Use a calorimeter to measure the temperature change in each of three reactions.
Aim : a) To determine reduction potentials of several redox couples. b) To determine the effect of concentration changes on cell potential. c) To determine the molar concentration of Cu2+ in the unknown using Nernst equation. Procedure : Please refer to the laboratory manual page 77 – 79. Results : Reduction Potentials of Several Redox Couples Galvanic Cell Measured Ecell Anode Equation for Anode Reaction Cathode Equation for Cathode Reaction Cu-Zn +1.19 V Zn Zn → Zn2+ + 2e- Cu Cu2+ + 2e- → Cu Cu-Mg +3.23 V Mg Mg → Mg2+ + 2e- Cu Cu2+ + 2e- → Cu Cu-Fe +0.89 V Fe Fe → Fe2+ + 2e- Cu Cu2+ + 2e- → Cu Zn-Mg +2.00 V Mg Mg → Mg2+ + 2e- Zn Zn2+ + 2e- → Zn Fe-Mg +1.54 V Mg Mg → Mg2+ + 2e Fe Fe2+ + 2e → Fe Zn-Fe +0.29 V Zn Zn → Zn2+ + 2e- Fe Fe2+ + 2e- → Fe Balanced net reaction Cu-Zn Zn (s) + Cu2+ (aq) → Zn2+ (aq) + Cu (s) Cu-Mg Mg (s) + Cu2+ (aq) → Mg2+ (aq) + Cu (s) Cu-Fe Fe (s) + Cu2+ (aq) → Fe2+ (aq) + Cu (s) Zn-Mg Mg (s) + Zn2+ (aq) → Mg2+ (aq) + Zn (s) Fe-Mg Mg (s) + Fe2+ (aq) → Mg2+ (aq) + Fe (s) Zn-Fe Zn (s) + Fe2+ (aq) → Zn2+ (aq) + Fe (s) Zn-Mg = + 2.00 V, Mg-Cu = + 3.23 V The cell potential of Zn-Cu = 3.23 V – 2.00 V = 1.23 V The measured cell potential of Zn-Cu = +1.19 V The value of the sum of the Zn-Mg and Zn-Cu cell potentials are nearly the same as the Cu-Mg cell potential.
Lab Partner: Jason Wallace 02/17/09 LAB ABSTRACT: In this experiment unknown substances were identified by performing different flame tests on known substances. The substances identity was obtained by placing salt solutions of a metallic ion and observing the color of the emitted photon light. INTRODUCTION: By placing atoms of a substance into a flame it can absorb energy and jump into an excited state; called a quantum jump. After absorbing energy and leaping into an excited state, the atoms return back to their original ground state by emitting a photon of light. According to the law of conservation of energy the same amount of energy used to make the quantum jump is released when the photon light is emitted.