Essay Molar Heat of Combustion of Alkanols (Hsc Chem)

The energy released during combustion reactions goes into the surrounding atmosphere because the energy does not disappear it simply goes into the atmosphere of a surrounding area. For example, during the Cheeto experiment the fire being released is the energy but when the fire is out the rest of that energy is moved onto its surrounding like people and the air. One observation that I made during my experiment was when the mass of Cheeto was too big and when the Cheeto began to burn it released its energy onto the can which heated the water inside and that also created energy because the water releases steam and that goes into the air and the people around it. The fire being released wasn't always as expected because if the Cheeto was too big

I will measure these individual alcohols by mass which will be measured in grams, I'll be making two readings of each alcohol before the experiment and after, which would tell me the mass lost and how much heat is produced. Dependent Variable, the things that I'll be measuring would be the temperature (oC) increase at the start and the final resting point once combustion has been stopped of each different alcohol being lit to heat the water in the copper calorimeter, and the mass before and after the experiment of alcohols. Fixed Variables, the things that I have chosen to keep the same in each individual experiment to keep it a fair test, is to keep the same amount of water being heated, the same copper calorimeter, as it may vary in conductivity, the height of the calorimeter, and the same amount of time for each

Calorimetry is the science of measuring the change in heat absorbed or released during a chemical reaction. The change in heat can tell us if the reaction is either exothermic - it released or heat into surroundings, or endothermic - it absorbed heat from surroundings. The device used to measure calorimetry is a calorimeter. A calorimeter can range from very expensive lab ones to coffee styrofoam cups but they are all tightly sealed in order to prevent heat from escaping.

    One possible source of error that can affect the results was that a mercury thermometer was used instead of an electronic one. The use of a mercury

Thermodynamics is “the study of the effects of work, heat, and energy on a system”. In Thermodynamics to find the temperature change I will use the formula: Q=MCT. In this formula Q represents the heat added, M is the mass, C is the specific heat, and Tis the change in temperature. From using this equation I will later figure out the uncertainties I have in this experiment using the formula: Amount of DataGiven (average data/ amount of data given) then you take the given and subtract it from the answer from the formula above, lastly you add it up and square root it. Next, you put it in this form: average data ± answer using the formula above. Lastly, I will use error bars on the graphs to represent the uncertainty of the graphs. Error bars are represented by this image:

Heat: The amount of energy associated with the movement of atoms and molecules in matter.

12. Determine the percent error using the equation and knowing that the actual specific heat of lead is 0.130 J/g(oC): (10 points)

The group first measured the masses of the four bouncy balls and then measured how high the ball bounced, being dropped at 20 inches, in room temperature and recorded the data. Then heated up water in a 250mL beaker using a hot plate to about 85-90 degrees Celsius, put the bouncy ball in a smaller beaker and held it in the water for five minutes, making sure not to get the ball wet, repeat this procedure for all four bouncy balls. After the five minutes were up, the masses of the balls were measured and then tested the ball to see if when the ball was heated, it might affect the height of the bounce. The results were recorded. Next, a 250mL beaker was filled up with water about half way and then put ice in the water to make it cool down to 5-10 degrees Celsius. A bouncy ball was then put in a smaller beaker and held the small beaker with the ball inside the ice water for five minutes, doing this for all four bouncy balls. After the time was up, the group again measured the mass and tested the height of the bounce and recorded the results. When dropping the ball to measure the height of the bounce, the ball was dropped from 20 inches for each trial in all three

As with many experiments that are performed in a setting where we cannot be exact on every measurement, error could arise from it. For instance, from this particular experiment, we needed to measure 5mL of water and 5mL of the borax mixture after it had cooled. Measuring 5mL with the bulb pipet that we were provided was not an exact measurement tool. The pipets provided were not calibrated and/or could have contained pockets of air with the assumed 5mL of water or solution.

The lab used methods of calorimetry in order to measure the temperature change of reactions and calculate the changes in

have five C-H bonds, one C-C bond, one C-O bond and one O-H bond. To

Even though the result of an experiment is accurate and matches the literature value, it does not mean that there were no mistakes made. As the difference of the percentage uncertainty and the percentage error suggests there were random errors made. First of them was the heat energy lost to the surrounding environment during the experiment process taking place. This caused the recorded highest temperature to be smaller than the actual highest temperature that was meant to reach. This could have been prevented by adding in more and perfect

We will be using 6 different fuels to heat up 100ml of water, and find out the changes of the temperature. We will measure the temperatures of the water before and after the experiment. We will burn heat the water for exactly 2 minutes, and check the changes in temperature. The change in temperature will allow us to work out the energy given off the fuel by using this formula:

This lab is performed in order to determine the total energy in a reaction between zinc and hydrochloric acid. The reaction is done twice, once to measure the heat of the reaction and again to determine the work done in the system. This is because Enthalpy equals heat plus work (∆H= ∆E+W). Heat and work can be broken down further into separate components so the equation used in lab is ∆H=mc∆T + PV. Many calculations are used in the lab to find out what cannot be measured directly (ex: volume). After all the calculations were complete it was shown to have a very small percent error.

The aim of this experiment was to test the heat of combustion over a period of time, and the energy required to combust alcohols with different carbon chain levels. It was hypothesised that the higher the carbon chain of the alcohol present, the faster the heat of combustion will occur. Meaning more energy will be released for a higher carbon chain. After calculating the results from the experiment it was found that the hypothesis was partially supported. The reasoning for this is as the alcohol that posses a higher carbon chain, generally increased there reaction rates. However there were a few exceptions to this rule.