Ethyl alcohol, also known as ethanol, is the active ingredient in alcoholic beverages. While you drink it when you consume things like beer, spirits and wine, drinking ethyl alcohol on its own is dangerous and could cause fatality.
Continue reading to learn the chemistry behind ethyl alcohol, from its chemical composition and manufacturing process to how it differs from isopropyl alcohol.
Is Ethyl Alcohol the Same As Ethanol?
Ethyl alcohol is another term for ethanol. It’s an organic compound that’s volatile, flammable, and recognised by its strong smell. Ethanol is the only type of alcohol that can be safely consumed by humans – in the form of alcohol beverages, that is. Pure ethanol is toxic and can cause comas or even death.
Other types of alcohol, such as isopropyl alcohol (IPA) and butyl alcohol, are highly toxic and cannot be consumed in any way. These alcohols can cause blindness and death even at very low concentrations.
Ethyl alcohol is one of mankind’s prehistoric discoveries that is still widely used today. The discovery of consuming alcohol for recreational purposes most probably predates the human species itself. In fact, some primate species are observed intentionally consuming fermenting fruits to get inebriated! This method of creating ethyl alcohol, through the fermentation of sugary foods, is still the most popular manufacturing method today and is known as sugar fermentation.
What is the Chemical Composition of Ethyl Alcohol?
Ethyl alcohol, or ethanol, is a relatively simple organic compound with the chemical formula C2H6O. The formula can also be written as a structural formula: CH3−CH2−OH or simply C2H5OH.
As you can see in the structural formula, an ethyl group is linked to a hydroxyl group. This follows the generalised formula for alcohol, which is CnH2n+1OH.
A more generalised formula of alcohol is R-OH. The R represents the hydrocarbon chain and the OH represents the hydroxyl group. The two groups form a 109-degree angle with each other, as shown in the illustration below:
Given its molecular compositions, the molar mass is empirically determined to be 46.069 g·mol−1. The molar mass can be approximated by adding the atomic weights of all its elements.
Carbon has an approximate atomic weight of 12 but since there are two carbons, the total carbon weight is 24. Meanwhile, oxygen has an atomic weight of 16 and hydrogen has an atomic weight of 1 – but since there are six hydrogen atoms, the total hydrogen weight is 6. Therefore, the molar mass is calculated as: 24+16+6 = 46.
What is Ethyl Alcohol Made From?
The most common way of producing ethyl alcohol is through the fermentation of starchy or sugary food products, such as grapes or rice. Fermentation is a complex biochemical process that involves a living organism. A fungi species (yeast) is used to ferment the starchy source. The simplified fermentation pathway is illustrated below:
Here are some of the most common types of alcoholic beverages and their fermented ingredients:
- Ale: Fermented from malt with hops
- Beer: Malted cereal grain, like barley, is used for fermentation, while hops are added for flavour
- Brandy: Typically distilled from wine or from any fermented fruit juice
- Gin: Distilled or redistilled from a variety of sources and typically flavoured with juniper berries and other aromatics
- Rum: A liquor distilled from products of sugarcane, such as molasses
- Sake: Derived from brewing rice and very popular in Japan
- Tequila: The popular Mexican liquor that’s distilled from blue agave
- Vodka: Distilled from starchy food such as mash of potatoes, rye or wheat
- Whisky: A liquor distilled from a mash of grain such as rye, corn, or barley
- Wine: One of the oldest and most common sources of alcohol, wine is the fermented juice of fresh grapes
The other pathway of manufacturing ethyl alcohol is through petrochemical processes, such as the hydration of ethylene as shown in the balanced formula below. Dilute sulphuric acid is used as a catalyst in this reaction:
Is Ethyl Alcohol Safe to Drink?
While ethyl alcohol is the active ingredient of alcoholic beverages, and the only type of alcohol that is safe to drink in this way, consuming pure ethanol may lead to coma or even death.
In alcoholic beverages, ethanol is safe to drink responsibly, but only up to a certain point. On average, a blood alcohol concentration of between 0.020 and 0.039% is safe. At this concentration, ethanol causes inebriation and a loss of inhibition. However, when the blood alcohol concentration reaches 0.25%, alcohol poisoning begins, causing a loss of consciousness. When it reaches 0.40%, a person will fall into a coma and may die.
Various individuals have different levels of alcohol tolerance before becoming intoxicated. Factors such as food and body weight affect the tolerance for alcohol consumption, so always drink responsibly and know your limit.
What is the Difference Between Ethyl Alcohol and Isopropyl Alcohol?
Both ethyl and isopropyl alcohol (IPA) are commonly used as disinfectants, particularly as rubbing alcohol. However, IPA is poisonous when ingested, even at very small concentrations.
Chemically, they’re very similar. Compared to ethanol (C2H6O), isopropyl alcohol has the chemical formula C3H8O, which can also be written as CH3CHOHCH3. As you can see, an isopropyl group is attached to a hydroxyl group. This is the simplest form of secondary alcohol where the alcohol carbon atom is attached to two other carbons.
Which is Safer, Ethyl Alcohol or Isopropyl Alcohol?
In terms of potential harm to humans, ethyl alcohol has the lowest associated risks, even at high concentrations. Therefore, ethanol is safer than isopropyl alcohol. Nonetheless, both are flammable and can irritate the mucous lining. While IPA should not be consumed at any concentration, ethanol similarly shouldn’t be consumed at high concentrations.
You should wear personal protection equipment, like goggles, when handling either alcohol. You must also avoid igniting either of these alcohols as they’re very flammable.
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