3 Smart Things: The Hidden Lives of Liquids

1. Most substances make a clean break between their liquid and solid states. But liquid crystals straddle the boundary: They flow smoothly, like water, while maintaining a crystalline structure. A tiny jolt of electricity aligns the molecules in the same direction and allows them to rotate light—an effect you see when the pixels in your LCD television or smartphone flip on and off to form pretty images.

2. Our body’s natural lubricant, saliva, does double duty by sloshing away bacteria and neutralizing your mouth’s acidity. There’s high demand for the liquid. Human salivary glands pump out about a quart a day—a Big Gulp! The dry-of-mouth can always purchase backup sprays, gels, and swabs on the $1 billion artificial saliva market.

3. Packed with enough dissolved oxygen, liquid becomes breathable. While water can’t hold the requisite O2, the synthetic oil perfluorocarbon can absorb three times more oxygen than blood, meaning you could survive prolonged submersion (and even take a selfie—perfluorocarbon doesn’t harm electronics). This property also makes doctors hopeful that the oil could one day help soothe the frail lungs of premature newborns.

Adapted from Liquid Rules: The Delightful and Dangerous Substances That Flow Through Our Lives, by Mark Miodownik, out February 19.

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