Investigating Factors Affecting the Heat of Combustion of Alcohols
PLANNING SECTION
Introduction
------------
Alcohols are organic substances, and consist of Hydrogen, Oxygen and
Carbon. All alcohols are toxic but the amount that can be tolerated by
the human body varies for different alcohols. For example drinking
small amounts of Methanol can lead to blindness and even death.
Ethanol is the only alcohol that can be drunk safely and is found in
all alcoholic drinks. Throughout this investigation I am going to
investigate to different factors that affect the breakdown of an
alcohol.
[IMAGE]e.g. Methane (HCO) + Oxygen (O2) Carbon dioxide (CO2) + Water
(H2O)
Aim
---
I am going to investigate increasing the chain length and see what
effect there is on the heat of combustion.
Preliminary Work
----------------
The point of preliminary work is to find out what things that I should
vary and keep constant. For my preliminary work I used computer
software called Focus Science Investigation 2. This software enables
you to simulate experiments. This means that I am able to quickly
carry out experiments to help in planning for my investigation.
----------------------------------------------------------------------
Alcohol
Temperature Increase (oC)
Mass of burner before exp. (g)
Mass of burner after
exp. (g)
Change in mass (g)
Methanol
20
170.00
167.08
2.92
Ethanol
20
170.00
167.77
2.23
Propan-1-ol
20
170.00
168.03
1.97
Butan-1-ol
20
170.00
168.16
1.84
Pentan-1-ol
20
170.00
168.24
1.76
Having found these results I then worked out the combustion per mole
of alcohol.
Alcohol
Mass of water heated (g)
Heat evolved during reaction (J)
Change in mass of burner
(g)
Combustion of one mole of alcohol (kJ/mole)
Catching Fire: How Coooking Made us Human by Richard Wrangham is a fresh perspective on the evolution of humankind. Wrangham has made a concentrated effort to prove that humans have evolved particular adaptations, like bipedalism, due to the introduction of cooked foods into their diet. In his book, he is legitimately arguing that humans are the way they are because early on in human evolution, early man discovered fire, discovered the joys of cooked foods, and developed all sorts of fascinating traits still being utilized today.
In the span of only a few pages, L.B. Church has given us an overview of the winemaking process. He has done so with sufficient detail for those in the chemistry community to follow along, yet still in a cursory enough manner as to not bog them down with the unnecessary. Written as if it were the procedure of an experiment, he has given enough information for the experiment to be repeated, tested, validated and improved upon. And that is almost assuredly his goal from the very beginning, as it must be for any published author in the chemistry community.
In the case, “Facing a Fire” prepared by Ann Buchholtz, there are several problems and issues to identify in determining if Herman Singer should rebuild the factory due to a fire or retire on his insurance proceeds. I believe that this case is about social reform and self-interest. I think that Singer needs to ask himself, what is in the firm’s best economic interests. There are several things to question within this case, what should Herman Singer do and why, should he rebuild the factory or begin retirement, if he rebuilds, should he relocate the firm to an area where wages are lower and what provisions, if any, should Singer make for his employees as well as for the community?
To gain reliable results we needed a temperature rise of 50 degrees centigrade in the quickest time. possible. Then we can do it. Using the Propanol burner with different volumes of water we. tested the flame at varying distances under the calorimeter measured.
one gram of water by 1ºC. I chose to use water because it is safe,
The data of all three unknown solutions resulted in measurements that were all off by at least 7% of the theoretical percentages. For example, the 1st unknown solution was supposed to consist of about 30% Ethanol and around 70% N-Propanol, though the actual data we received put Ethanol at 20% and N-Propanol at around 80%. This 10% margin of error could have been caused by a multitude of mistakes including the liquid evaporating before it was injected, cross-contamination, bubbles within the needle, and students not clicking the button simultaneously as they injected the alcohol. Our teacher warned us about how quickly the alcohols evaporated from the needle and told us to keep our hands at the back of the syringe to prevent as much evaporation
The Enthalpy Change of Different Alcohols My aim is to compare the enthalpy change of combustion of different alcohols in relation to the structure of each molecule. The enthalpy change of combustion of a fuel is a measure of the energy transferred when one mole of the fuel burns completely. In a chemical reaction, bonds must either be made or broken, this involves an enthalpy change. The formation of bonds is exothermic, energy is lost to the surrounding; on the other hand, breaking bonds is endothermic, energy is taken in. I obtain the value for the enthalpy change of each fuel by using the formula: Energy transferred from the fuel=
For the sample calculations, let’s use the marshmallow as an example. Its initial mass was 0.66 grams and its final mass was 0.36 grams. To calculate the amount burned, subtract 0.36 from 0.66 to get 0.30 grams. (Mass burned = mi- mf). To find the marshmallow’s change in temperature, use the formula (ΔT =
Do you know what alcohol does to a human body over time? Alcohol has many characteristics that affect people differently. The different kinds of alcohol will affect individuals differently because of other variables such as body physique, how full one’s stomach is and how quickly the alcohol is consumed. Alcohol is considered to be a drug. It is under the class of a depressant, which means it slows down the vital functions. After drinking too much, alcohol can slur speech, produce unsteady movements, disturb perception, and slow reaction time. It also reduces a person’s ability to think rationally and distorts his or her judgements. Blood alcohol concentration is used to determine the level of intoxication of an individual by the weight
Input variables In this experiment there are two main factors that can affect the rate of the reaction. These key factors can change the rate of the reaction by either increasing it or decreasing it. These were considered and controlled so that they did not disrupt the success of the experiment. Temperature-
reaction is the rate of loss of a reactant or the rate of formation of
The oxygen atom is joined to the hydrogen atom as well as the carbon atom, which makes the oxygen a part of a hydroxyl group. These atoms are generally part of a hydrocarbon chain. These alcohols can take away water from the body, in which a hydrocarbon chain has replaced a hydrogen atom. Alcohols have a general structure of CnH2n+1OH. The aim of this investigation is to see the link between the number of carbon atoms in a fuel with the amount of energy it releases.
Alcohol is an ethanol containing substance that is a common beverage in many social and private settings. Alcohol is also a teratogen, therefore alcohol co...
Pyrolysis is a rapid thermal decomposition process of organic biomass, in absence or little supply of oxygen, brought about by high temperatures into useful biofuel products such as pyrolysis oil, ethanol, biodiesel, methanol etc. During the process, large hydrocarbon molecule’s chemical composition structure breaks down into relatively smaller molecules into solid (char), liquid or gas phase (Figure 1). The process is very similar to many other biomass decomposition processes such as torrefaction, carbonization, devolatilization etc. however pyrolysis cannot be compared to gasification due to external activation required for gasification.
Alcohol is a class of organic compounds that is characterized by the presence of one or more hydroxyl groups (-OH) attached to a carbon atom. Alcohol was unknowingly produced centuries ago when fermentation occurred to crushed grapes (Pines, 1931). In today’s society alcohol is produced for the use of household products such as varnishes, cleaning products, but is more commercially important in the liquor business. A chemical process called fermentation accomplishes the production of ethanol, the alcohol or liquor. From there, the ethanol goes through distinct processes to become the dark and clear liquors on the store shelves.