Heat of Combustion Experiment

1. Which reactants used in this experiment are flammable? Discuss the safety precautions that are necessary when working with flammable materials in the lab?

An Investigation into the Enthalpies of the Combustion of Alcohols = == == == ==

    In this lab, a calorimeter was used to find the enthalpy of reaction for two reactions, the first was between magnesium and 1 molar hydrochloric acid, and the second was between magnesium oxide and 1 molar hydrochloric acid. After the enthalpy for both of these were found, Hess’ law was used to find the molar enthalpy of combustion of magnesium, using the enthalpies for the two previous reactions and the enthalpy of formation for water. The enthalpy of reaction for the magnesium + hydrochloric acid reaction was found to be -812.76 kJ. The enthalpy of reaction for the magnesium oxide + hydrochloric acid reaction was found to be -111.06 kJ. These two enthalpies and the enthalpy of formation for water were manipulated and added together using Hess’s law to get the molar enthalpy of combustion of magnesium. It was found that the molar enthalpy of combustion of magnesium was -987.5 kJ/mol. The accepted enthalpy was -601.6 kJ/mol, which means that there is a percent difference of 64%. This percent difference is very high which indicates that this type of experiment is very inefficient for finding the molar enthalpy of combustion of magnesium. Most likely, a there are many errors in this simple calorimeter experiment that make it inefficient for finding the molar enthalpy of combustion of magnesium.

If you went out one day and out of nowhere you find yourself in a life-or-death situation would it be your fault? People in a life-or-death situation should be held accountable for their actions because most of the time people know that if they do something that can put them in a life-or-death situation then something bad will happen but they still do it willingly. Another person might not agree with this claim and say that people should not be held accountable for their actions. The reason he or she might think this is because if when a person does face a life-or-death situation it might not be entirely their fault. The following reasons are examples of why my claim is stronger.

To begin with, I believe that there was more than one conflicts in the story. The conflicts were man vs. nature, man vs. self, man vs. man, and man vs. society. Mattie acquired all of these conflicts throughout the novel. To describe the conflict of man vs. nature, it is explained that the fever had spread through the air and it was up to Mattie to save herself from the disease. She had to “fight” nature and protect herself from the heat as well as the fever until winter arrived. Mattie also fought with herself when she had to decide to give Nell up to the orphanage or keep her in her own hands. Mattie also shows man vs. society as she defended the intruders breaking in the coffeehouse. Man vs. man is explained in the novel when Mattie would argue about doing her chores and going to Polly’s funeral in the

Because it is dangerous to burn magnesium, it is not possible to directly record heat change. Our lab team suggests an indirect way of determining the heat of combustion for magnesium. To accomplish this, we need to perform two separate trials. One uses a solid (powder) version of MgO, while the other uses Mg ribbon. With the results from these, we can use Hess’ Law to determine q=∆H. This provides both a safe and successful way of indirectly determining the heat of combustion for magnesium.

The burn rate of the mixture was recorded with a video camera and the results recorded and timed. The resulting footage was reviewed and the duration of the combustion noted on a tenth of a second basis. 4 grams of Alliant Green Dot double-base smokeless flake powder with no KClO4 added was also recorded twice in the same manner, to give a baseline burn time and averaged.

Seven7 inched long, long high jumping, and a master of light manipulation, Pepe can definitely beat any super villain that comes his way. Being a frog is hard, but not for Pepe. With his frog like body, and only being Seven7 inches long, you bet that his jumps are out of this world. If Scorcher, the evil villain, were to attempt to use his fire against Pepe, the frog like man can just spring out of harm’s way. From high to low, fast or slow, either way, his jumps will lead him to some format of safety. Scorcher can attempt his fire usage all he would like to, but in the end all that will happen would be everything ending up in fire and Pepe being fire free. Just like how he prefers to be.

On March 25, 1911, at 4:45 pm there was a fire that broke down at the triangle shirtwaist factory located in NYC Asch Building at 23-29 Washington Street were engulfed in flames. First, the fire started 8th floor and on to the 9th then 10th which was occupied by triangle waist company. Second, the fire killed 146 people and most of them were females between the ages of 15-25 years old. Lastly, the owners Harris and blanck were guilty of this crime in my opinion and the government didn’t help the victims of the fire in their company.

Qualitative Observation of a Chemical Reaction Introduction Procedure: 1. Record the appearance, odor and feel of the unlit candle. 2. Heat the bottom of the candle and secure it to the glass square. 3.

The objective is to determine the presence of a cation and anion by a chemical reaction through determining the presence of the cations and anions in an unknown salt.

Jack Zhou Eric Lonrenzo Chemistry section # Date Chemical Reactions Introduction: The purpose of the lab was to create and observe the 4 kinds of chemical equation, and to identify reactants and products of those reactions.

Procedure: We held our plastic over the flame and observed the way our plastic burned.

In this project we examined three explanations that talk about (a) candle(s) in a jar and their investigation reasoning to why the labs they did were concluding in such a way. The first explanation resulted that the candle inside the jar took up all the oxygen molecules inside the flask which then lowers the pressure inside and the higher pressure outside the flask is what causes the water to rise up. The second explanation resulted in that the air pressure increases inside the jar because of the heat from the candle, which causes air to come out of the jar and once the candle cools down the pressure decreases and the pressure outside the jar increases which results in pushing the air in and making the water rise up. The third explanation resulted in oxygen inside the flask becoming carbon dioxide which then dissolves in water causing the air pressure to decrease under the glass and the higher pressure outside the flask pushed the water up the flask. I believe that explanation number three is right because the flame causes carbon dioxide to be created and that

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.