The universe cheats. Because the molecules of water and alcohol love each other (thanks to hydrogen bonding), they pack together more tightly than they do with their own kind. The water molecules slip into the spaces between the ethanol molecules.
At first glance, the number seems trivial. The density of pure (anhydrous) ethyl alcohol at room temperature (20°C / 68°F) is approximately . But don't let the "0.789" fool you. This tiny decimal point is a chemical rebel, and its behavior tells a fascinating story. The Rebel Who Floats Let’s start with the most obvious magic trick: density is why your "heavy" rocks sink and your "light" cork floats. Water has a density of 1.00 g/cm³. Ethanol, at 0.789, is significantly lighter. alcohol etílico densidad
Cheers to 0.789.
When you hear "ethyl alcohol" (or ethanol), your mind probably jumps to one of two places: a stiff glass of whiskey or the sterile sting of hand sanitizer. But hidden within this simple molecule—C₂H₅OH—lies a physical property that dictates everything from the price of your vodka to the safety of space travel: density. The universe cheats
You get roughly 960 ml.
Ethyl alcohol expands with temperature much faster than water does. A hydrometer calibrated for 20°C will lie to you if you test a warm spirit at 30°C. It will read a lower alcohol content than what is actually present because the hot liquid has expanded, lowering its density. At first glance, the number seems trivial
The density of ethyl alcohol isn't just a number on a safety data sheet. It is the physics behind the pleasure, the science behind the safety, and the reason your ice cubes sink in a glass of Coke but almost float in a glass of Everclear.