Showing 47 posts tagged chemistry

From “science on a budget” YouTuber Nick Moore, watch this drop of mercury being vibrated from ~120Hz down to ~10hz. We’ve seen resonance demonstrated before in Chladni Pattern videos: sound frequencies become visualized as patterns via the vibrations. Higher frequencies = more complex shapes and patterns. Adam Frank explains in more detail at NPR:

In the video above, sound waves passing around and through a drop of mercury set it oscillating. But the physics of the system — determined by things like the speed of sound in mercury and the strength of its surface tension — allow some sound waves to excite special vibrations in the drop. In other words, the mercury drop has resonances with the sound at specific frequencies.

These are called the resonant modes of the drop. When the frequency of the sound waves matches the frequency of the drop’s resonant modes, highly organized patterns of pulsation are triggered. You know you’ve hit strong resonances when something like a multiple-armed, star-shaped pattern emerges.

It’s a remarkable reminder of the hidden architectures embedded in the world around us.

In the archives: sculpting in solid mercury, with liquid nitrogen and videos about the elements.

Maple trees + good timing + basic chemistry = maple syrup. But Science Friday takes us behind the scenes of maple syrup research to show that there’s much more to it than that. While the tradition has been to tap fully grown wild trees – commercially with lots of plastic tubing – recent experiments at University of Vermont’s Proctor Maple Research Center have found that harvesting from the cut tops of juvenile trees might yield 5 to 6 times per acre, surprisingly without harming the young trees.

Lots of questions about this one: What are the other differences between the farm vs forest model of growing trees? Does this new process affect the local birds or creatures underground? What do these young trees look like in 20 years? What questions do you have?

File under: food, trees, and how things are made.

From Science Friday.

We know that sugar is a big part of candy, ice cream, and sweet drinks, but did you know that added sugars are included in 3/4 of the 600,000+ products found in the average grocery store? And that it can go by 56 different names? 

Watch this super useful TED Ed by Robert Lustig, with animation by The Tremendousness Collective, to learn more about the different kinds of sugar inside the foods that we eat, and how it interacts with our bodies: Sugar: Hiding in plain sight.

Related watching: The Cook’s Atelier, China’s farm to table movementHow Gardening Enables Interdisciplinary Learning, and more TED Ed videos.

From the team at Kurzgesagt, let’s explore what we know about The Beginning of Everything — The Big Bang:

Has the universe a beginning or was it here since forever? Well, evidence suggests that there was indeed a starting point to this universe we are part of right now. But how can this be? How can something come from nothing? And what about time? We don’t have all the answers yet so let’s talk about what we know. 

Previously on this site: Take a trip through The Solar System — our home in space, plus more about The Big Bang, including Carl Sagan’s cosmic calendar and the last five minutes of How the Universe Works: Extreme Stars.

Thanks, Philipp.