Ethanol
Definition and meaning of Ethanol in chemistry.
Ethanol is a clear, flammable liquid that belongs to the organic group called alcohols. The chemical has a strong smell and serves as the main active ingredient in alcoholic drinks. This simple molecule has a two-carbon ethyl group attached to a polar hydroxyl group.
In more detail
The polar hydroxyl group contains oxygen and hydrogen atoms with uneven electrical charges. This polar nature allows the molecules to form strong hydrogen bonds with each other. These strong bonds give the liquid a relatively high boiling point for its size.
The hydrogen bonds also let ethanol mix perfectly with water in any amount. Living things make ethanol from plant sugars through a process called anaerobic fermentation. Yeast cells perform this chemical reaction without using any oxygen to get energy to live.
Breweries use this natural yeast process to produce beer and wine for consumers. Chemical factories can also make pure industrial ethanol from ethylene gas. They add water to the gas using an acid catalyst to speed up the process.
Scientists use this pure ethanol in laboratories to dissolve things that water cannot. Energy companies mix ethanol into normal gasoline to create a cleaner burning fuel. This mix adds oxygen to the fuel, which helps the gasoline burn more completely.
The extra oxygen lowers the amount of toxic carbon monoxide that comes out of car tailpipes. Inside the human body, the liver breaks down ethanol using special proteins called enzymes. An enzyme called alcohol dehydrogenase turns the alcohol into acetaldehyde, which is a highly toxic chemical.
The body then quickly changes this toxic chemical into a harmless substance called acetate. A common student misconception is that all alcohols are safe to drink. In reality, other alcohols like methanol are highly toxic even in tiny amounts.
Key facts
| Field | Organic Chemistry |
|---|---|
| Formula | C2H5OH |
| Molar mass | 46.07 g/mol |
| Boiling point | 78.37 °C |
| Density | 0.789 g/cm³ |
E85 is a common fuel blend sold at gas stations across the country. It contains 85 percent ethanol mixed with 15 percent normal petroleum gasoline. Car manufacturers build special flexible-fuel engines that can run on this specific blend.
Frequently asked questions
Why do hand sanitizers use ethanol?
Ethanol breaks open the protective fat layer around cell walls. It also destroys important proteins inside the cells to kill bacteria and viruses. Hand sanitizers work best when ethanol is mixed with water at sixty to eighty percent.
Why does ethanol mix perfectly with water?
The polar hydroxyl group easily forms strong hydrogen bonds with water molecules. Ethanol also has a short carbon chain that is nonpolar and hydrophobic. The strong polar bonds are much stronger and force the liquids to mix completely.
What is the difference between ethanol and denatured alcohol?
Denatured alcohol is ethanol that has toxic additives mixed into it. These additives make the liquid dangerous to drink so stores can sell it without alcohol tax. It remains useful for industrial cleaning or as a fuel for small camp stoves.
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