Section 1-Just the Facts
- The molecular formula for ethanol is C2H6O.
- Ethanol is made of three different elements, hydrogen, carbon and oxygen. In ethanol there are two carbon atoms, six hydrogen atoms and one oxygen atoms.
- All the elements that make up ethanol are non-metals therefore making ethanol a covalent compound.
- Ethanol is used by automotive vehicles because it can be used as fuel in the motor. Ethanol can also be used as a disinfectant since it is 95% alcohol.
- Chemical and Physical Properties-This compound is a colorless liquid with a pleasant smell. It is completely miscible with water and organic solvents and is very hydroscopic. The melting point for ethanol is -117.3 degrees celsius. The boiling point is 780 degrees celsius, Ethanol burns with a pale blue, non luminous flame to form carbon dioxide and steam. It is also miscible with water in all proportions and is separated from water only with difficulty. Absolute ethanol is when ethanol is completely free of water.
- Molar Mass-46.07 g·mol−1
- Appearance-Colorless liquid
- Density-0.7893 g/cm3 (at 20 °C)
- Melting Point−114.14 ± 0.03 °C (−173.45 ± 0.05 °F; 159.01 ± 0.03 K)
- Boiling Point-78.24 ± 0.09 °C (172.83 ± 0.16 °F; 351.39 ± 0.09 K)
- Vapor Pressure-5.95 kPa (at 20 °C)
- Acidity- (pKa)15.9 (H2O), 29.8 (DMSO)
- Basicitity-(pKb)−1.9
- Magnetic suscepitibility- (χ)-33.60·10−6 cm3/mol
- Different names for ethanol are ethyl alcohol, isopropyl alcohol, grain alcohol, rubbing alcohol, carbon disulfide and ammonia alcohol.
- Ethanol can be classified as organic because the hydrogen and carbon atom form a hydrocarbon. Ethanol is also know as a non-electrolyte because it does not form an ion thus it does not produce electrolytic solutions. Ethanol is a toxic compound because it can be toxic with skin contact and ingestion in it's pure form. (Whole Section=1)
Section 2- A Little More
- Ethanol is harmful because it is alcohol and alcohol can result in bad situations.(2)
- Ethanol's is useful because it can be used as a disinfectant to clean wounds.(2)
- There are many products that contain ethanol. These products are mostly household products. Some examples of these products are body lotions, bath salts, shampoos, perfumes, and much more. Ethanol is also used as an automotive fuel. (5)
- Ethanol can be fermented from many sources of starch, including corn, wheat, grain sorghum, barley, and potatoes, and from sugar crops such as sugar cane and sweet sorghum. Because there has been has been an abundant supply of corn, most of the ethanol made in the United States is from corn.(1)
- The U.S. ethanol industry has grown from a handful of small plants producing 350 million gallons to 200 plants producing a record 15.3 billion gallons of ethanol in 2016.(4)
- Today, we make up 10% of the U.S. gasoline supply, up from less than 1% just over 20 years ago.(4)
- Blended in 97% of gasoline today, all across the country, ethanol is driving energy independence. In 2016, ethanol displaced gasoline refined from 540 million barrels of crude oil.(4)
- Today’s ethanol producers get more ethanol out of every bushel and use less energy and water to do it. Over the past two decades, the environmental impacts of producing ethanol have been greatly reduced. Meanwhile, the ecological impacts of petroleum extraction, refining and use continue to worsen.(4)
- In the first century A.D., the Greeks and the Arabs discovered distillation, a process to increase the ethanol content of alcoholic drinks.(4)
- Ethanol can be made by reacting ethene (from cracking crude oil fractions) with steam. A catalyst of phosphoric acid is used to ensure a fast reaction. Notice that ethanol is the only product. The process is continuous – as long as ethene and steam are fed into one end of the reaction vessel, ethanol will be produced.(4)
- Carbon->hydrogen is a covalent bond(1)
- Hydrogen-> oxygen is a covalent and hydrogen bond(1)
- Carbon-> oxygen is a covalent bond(1)
- The molecular formula for ethanol is C2H6O. To find ethanol's molar mass, find the mass of each element. Carbon's mass is 12.011. Hydrogen's mass is 1.0079. Oxygen's mass is 15.999. Add these numbers up to get the molar mass. 12.011(2)+ 1.0079(6)+ 15.999= 46.06844. The molar mass of ethanol is 46.06844. ( 4)
Section 3- Having Fun with your Compound
- If a small piece of sodium is dropped into some ethanol, it reacts steadily to give off bubbles of hydrogen gas and leaves a colourless solution of sodium ethoxide, CH3CH2ONa. Sodium ethoxide is known as an alkoxide.
Although at first sight you might think this was something new and complicated, in fact it is exactly the same (apart from being a more gentle reaction) as the reaction between sodium and water - something you have probably known about for years.
Compare the two:
We normally write the sodium hydroxide formed as NaOH rather than HONa - but that's the only difference.
Sodium ethoxide is just like sodium hydroxide, except that the hydrogen has been replaced by an ethyl group. Sodium hydroxide contains OH- ions; sodium ethoxide contains CH3CH2O- ions.
Sodium ethoxide is just like sodium hydroxide, except that the hydrogen has been replaced by an ethyl group. Sodium hydroxide contains OH- ions; sodium ethoxide contains CH3CH2O- ions.
- Ethanol is a very polar molecule due to its hydroxyl (OH) group, with the high electronegativity of oxygen allowing hydrogen bonding to take place with other molecules. Ethanol therefore attracts polar and ionic molecules. The ethyl (C2H5) group in ethanol is non-polar. Ethanol therefore attracts non-polar molecules. Thus, ethanol can dissolve both polar and non-polar substances. In industrial and consumer products, ethanol is the second most important solvent after water.
- Three types of intermolecular bonding occur between ethanol molecules: dipole-dipole, hydrogen bonding, and London dispersion forces.Dipole-dipole forces are attractive forces between the positive end of one polar molecule and the negative end of another polar molecule.Hydrogen bonding occurs between the attraction of the proton in the hydrogen atom and the lone pair of electrons on an oxygen atom. London dispersion forces are the weakest type of intermolecular force.
- There are two types of bonds in ethanol. The C-H bonds are non-polar covalent, since these atoms are of similar electronegativity (the ability of an atom to attract electrons to itself when it is bonded to another atom in a compound.) The C-O and O-H bonds are polar covalent since O is significantly more electronegative than either C or H. Hence there is a slight + charge (d+) on the C and H attached to the O and a slight - charge (d-) on the O.
- In the Lewis structure, the carbon and oxygen atoms are surrounded by eight electrons (an octet of electrons, or four pairs), leading to the stability of these atoms in comparison to atomic C and O which have 4 and 6 outer shell electrons respectively. (C is in group 4 and oxygen in group 6 of the periodic table.) H has a duet of electrons. Since these atoms are nonmetals, they achieved filled outer shell through the sharing of electrons.
- The formal charge on each atom in ethanol is zero. This is calculated by assigning electrons to each atom in ethanol and comparing the number assigned each atom to the number found in the outer shell of the lone atom unbonded. Lone pairs are assigned to the atom they are placed around in the Lewis structure. Bonded electrons are divided equally between the two atoms in the bond. If atom in a molecule are assigned more electrons than the lone atoms has in its outer shell, it would have negative charge equal to the excess number of electrons. Positive charges develop when they are assigned fewer.
- With 8 electrons (4 pairs) surrounding the C and O of ethanol, the geometry of the electrons clouds around the C and O are tetrahedral, with bond angles of approximately 109o. In this arrangement, the electrons clouds, which repel each other, are as far apart as possible. Since 4 atom are attached to each carbon, the geometry of the atoms around the C is also tetrahedral. However, only two atoms (C and H) are attached to the O, so the geometry of the atoms around the O is bent or angular. This geometry shows that their is a separation of the center of slight positive and slight negative in the molecule, which makes this molecule polar. (Whole Section=3)
Section 4- The Finish Line
- This project helped me learn a lot more about my pet compound. I liked how it helped me learn about everyday things that my compound helps with. I also liked learning all the interesting facts about my molecule that I never knew.
- The most interesting thing I learned about my pet compound was that ethanol was used in gasoline to power motored vehicles.
- My molecule taught me that all molecules have different characteristics. Not all compounds do the same thing so I thought that was very interesting to learn ethanol's different characteristics.
- This project showed me chemistry is relevant in everyday life because I learned that ethanol is used in gasoline to power motored vehicles and I never knew that compound was helpful in everyday life.
- An experiment I would like to do with ethanol is fueling a small rocket with ethanol gas and seeing how that turns out.