Experiment-1-Heat-of-Combustion step by step PDF

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EXPERIMENT 1: HEAT OF COMBUSTIONIntroduction:The Heat Of Combustion is the liberated energy that occurs when a substance undergoes complete combustion, usually in an oxygen – rich environment, at constant pressure. This value is used to quantify the performance of a fuel in combustion systems (e. mo...

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Group 4

EXPERIMENT 1:

HEAT OF COMBUSTION

Introduction: The Heat Of Combustion is the liberated energy that occurs when a substance undergoes complete combustion, usually in an oxygen – rich environment, at constant pressure. This value is used to quantify the performance of a fuel in combustion systems (e.g. motors, engines in cars, turbines). Fuels are materials that are used to release energy (work or heat) via a chemical reaction. These makes fuels a very crucial group of substances especially in the modern civilization. Common fuels include gasoline, petroleum, and diesel. These fuels are commonly composed of hydrocarbons of differing molecular weights and other organic compounds. Combustion of these hydrocarbons gives off carbon dioxide and water as its major products, with a release of large amounts of heat. In efforts to reduce gas consumption from oil, ethanol is often added to regular gasoline. It has a high octane rating and burns more slowly than regular gas. This "gasohol" is widely used in many countries. It produces somewhat lower carbon monoxide and carbon dioxide emissions, but does increase air pollution from other materials. Molar Heat of Combustion Many chemical reactions are combustion reactions. It is often important to know the energy produced in such a reaction so we can determine which fuel might be the most efficient for a given purpose. The Molar Heat Of Combustion is the heat released when one mole of a substance is completely burned. Typical combustion reactions involve the reaction of a carbon-containing material with oxygen to form carbon dioxide and water as products. If methanol is burned in air, we have:

In this experiment, the heat of combustion of common fuels (which are not normally seen as fuels per se) would be studied, using a simple calorimeter model.

Objectives: Determine heats of combustion of a 70% isopropyl alcohol.

Group 4 Personal Protective Equipment: Laboratory gown, heat resistant gloves, eye protection

Methodology 1) Measure 100 mL of water and pour it inside a clean, dry aluminum can (use the softdrinks in can- only the can). Record the initial temperature of the water. 2) Fill the fuel lamp (Alcohol Lamp) with 70% isopropyl alcohol. Record the volume of the fuel. 3) Settle the aluminum can on top of the tripod, while the fuel lamp in the bottom. Ignite the lamp, making sure the fire reaches the aluminum can. 4) Stir the water gently with the thermometer and watch the temperature. When the temperature has increased by 20 °C, put off the flame of the lamp. 5) Record the mass final volume of the fuel. 6) Compute for the energy transferred to the water by the equation q = mH2OCpΔT Assume that the density of water is 1.00 g /mL, and the specific heat is 4.18 J / g・°C. The relative density (water =1); 70% isopropyl alcohol is 0.79.

7) Picture your set up and performance, paste it and submit as a Microsoft Word. 8) Practice precautions and always be careful in performing your experiment.

ASSIGNMENTS, Watch this video for further education, information and review: EXAMINATION’S and QUIZZES will be based from these VIDEOS…

Heat of Combustion https://www.youtube.com/watch?v=zeG0mUsSMmg&feature=youtu.be NOTE: -This video is just an example of what really happens inside the laboratory - You will not perform exactly the same - You will be using Aluminum can (use the soft drinks in can- only the can) - Practice precautions and always be careful in performing experiments

Group 4 Name: Jubilo, Denis Ira, R. (Assistant) Daza, Ronnie Jr. (Leader) Salazar, Yliza Nicole (Assistant) Members: Velasquez, Daniella Francine Cando, Irish Micole Merque, John Ric Robles, Rex Imman Course/Year/Section: BSCOE, 1st Year, 1-6

Activities and Assessments:

Date: November 14, 2021

Professor: Prof. Ferrie Oliva

EXPERIMENT 1

Equipment

Figure 1. All equipment that will be used in the experiment.

Figure 2. Aluminum can in the top of the improvised tripod with an alcohol lamp underneath.

Group 4 

Wooden Stick

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Matches

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Aluminum Can

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100 mL of Water

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Infrared Thermometer

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Alcohol Lamp

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70% Isopropyl Alcohol

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Weighing Scale

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Medicine Cup

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Improvised Tripod with Wire

Methodology 1) Measure 100 mL of water and pour it inside a clean, dry aluminum can (use the softdrinks in can- only the can). Record the initial temperature of the water.

Figure 3. Front view of the aluminum can.

Figure 4. Top view of the aluminum can.

Group 4 2) Fill the fuel lamp (Alcohol Lamp) with 70% isopropyl alcohol. Record the volume of the fuel.

Figure 5. 70% Isopropyl alcohol and alcohol lamp.

Figure 6. Alcohol lamp on a weighing scale.

Figure 7. Top view of the alcohol lamp on a weighing scale.

Group 4

Figure 8. Initial volume of the fuel.

3) Settle the aluminum can on top of the tripod, while the fuel lamp in the bottom. Ignite the lamp, making sure the fire reaches the aluminum can.

Figure 9. Aluminum can on the top of the improvised tripod while heating with alcohol lamp.

4) Stir the water gently with the thermometer and watch the temperature. When the temperature has increased by 20 °C, put off the flame of the lamp.

Figure 10. Temperature of the water after heating.

Group 4 5) Record the mass final volume of the fuel.

Figure 11. Alcohol lamp placed on top of the weighing scale.

Figure 12. Final volume of the fuel measured on the weighing scale.

6) Compute for the energy transferred to the water by the equation q = mH2OCpΔT Assume that the density of water is 1.00 g /mL, and the specific heat is 4.18 J / g・°C. The relative density (water =1); 70% isopropyl alcohol is 0.79.

7) Picture your set up and performance, paste it and submit as a Microsoft Word. 8) Practice precautions and always be careful in performing your experiment.

Group 4 GIVEN:

Table 1. Initial and Final Volume of Fuel

Initial Volume Final Volume

FUEL 150 g 149 g

Table 1. Initial and Final Temperature of Water

Initial Temperature Final Temperature

WATER 22.7 °C 42.7 °C

Volume of water = 100 mL Density of water = 1.00 g /mL Specific heat = 4.18 J/g • °C Relative density (water) = 1 Fuel (isopropyl alcohol) = 0.79

Questions 1) For each replicate experiment, perform the following calculations: a. The mass of the fuel burnt, mfuel b. The amount of moles of the fuel burnt, nfuel

c. The molar enthalpy of of the fuel by the equation

2) Would there be a change in the value of the enthalpy of combustion if the water is heated until a 30 °C change is observed, rather than 20 °C? Why or why not?...