/oss/taxonomy/term/2027/all en /oss/article/general-science/bubbling-over-science <p>Bottled soft drinks that lose their fizz also lose their appeal. But it seems technology has come to the rescue with the “Fizz Keeper.” This little pump can be fitted into the neck of the bottle and with a few deft strokes the air space above the liquid can be pressurized. Soon the bottle feels as rigid as a fresh, unopened one. A pretty convincing effect. But does this device really put an end to the disappointment of finding a flat beverage in the fridge? I’ll let that question simmer while we take a little detour into the fascinating world of bubbles.</p> Tue, 09 Jul 2024 02:43:13 +0000 Joe Schwarcz PhD 9997 at /oss /oss/article/you-asked/can-coffee-really-explode-microwave <p>This is due to a phenomenon known as superheating. First, we have to understand what boiling is all about. At the surface of a liquid molecules are always evaporating. If we leave a glass of water out, it will eventually disappear. If we heat the liquid, its molecules move faster, become more energetic and more molecules go into the vapour phase. As a consequence, the liquid disappears more quickly. At the boiling point, molecules all over the liquid, not only at the surface are energetic enough to go into the vapour phase.</p> Thu, 06 Dec 2018 17:00:50 +0000 Joe Schwarcz PhD 7478 at /oss /oss/article/controversial-science-health-quackery/should-one-worry-about-reboiling-water-coffee-or-tea <p>An article is circulating on the internet about the dangers of reboiling water and concentrating dissolved chemicals. It amounts to baseless fear-mongering. Lets consider fluoride as an example. Suppose you put a liter of water containing 1 ppm fluoride in a kettle and boil it. You then take 200 mL to make a cup of coffee or tea. That means you will ingest 0.2 mg of fluoride. If you now let the water keep boiling until 100 mL evaporates...which would take a long time...and you take 200 mL from the remaining water to make your next cup of coffee, you will be ingesting 0.22 mg of fluoride.</p> Tue, 30 Jun 2015 08:29:31 +0000 Joe Schwarcz 2269 at /oss