Alfredo Mateus 🧪⌬

Professor de Química do Coltec-UFMG, autor de livros de experimentos, entusiasta da ciência

[Alfredo Mateus 🧪⌬ @alfmateus]

Conheça o https://t.co/7ufHtkaIWy, meu blog com recursos para o ensino de ciências. Experimentos, abordagem maker, uso de TICs em sala de aula e mais.

[Alfredo Mateus 🧪⌬ @alfmateus]

@Andrestrujado Do you use some special kind of Tesla coil? I tried it with a small one and it did not work.

[Alfredo Mateus 🧪⌬ @alfmateus]

@justfredimelda I would prefer just the title on a black background than AI crap.

[Alfredo Mateus 🧪⌬ @alfmateus]

@Andrestrujado @nanocotech Do they sell this demonstration kit? I am putting together an exhibit for the International Year of Quantum Sciences here in Brazil and this experiment is on my list, if I can find a source.

[Alfredo Mateus 🧪⌬ @alfmateus]

Sent my proposal for a presentation @ChemEd2025 today! ChemEd is the best conference for chemistry teachers that I have been. Looking forward to the conference and to get to know Colorado.

[Alfredo Mateus 🧪⌬ @alfmateus]

@Joe_____D only saw your post now, sorry... The files are here: https://t.co/7elMIszkTR

[Alfredo Mateus 🧪⌬ @alfmateus]

Today is laser day. I am at our school's makerspace cutting some resources for my Chemistry classes. Lots of nice things you can do with a laser cutter/engraver.

[Alfredo Mateus 🧪⌬ @alfmateus]

I made some Avogadro Number scrolls. A long banner with some 3D printed parts that fit on the wood bars on each edge. The idea is to make a slow reveal of the number in class, thousands, millions, billions.... up to 602 sextillions.

[Alfredo Mateus 🧪⌬ @alfmateus]

The students are doing an evaluation using microscale reactions today. They have to describe what they observe and draw models of what happens. Just like @UncleBo80053383 Power point animations.

[Alfredo Mateus 🧪⌬ @alfmateus]

@agbrolo @chemistryatuvic Congratulations, Brolo!

[Alfredo Mateus 🧪⌬ @alfmateus]

@MrShepherdChem @StAmbroseSci @SSERCofficial If you use music you can make really build the end of the series. You can "tune" the last one for the end of the music. William Tell Overture. Got the idea from an old JChemED article. https://t.co/xqFyv3fORS

[Alfredo Mateus 🧪⌬ @alfmateus]

This is my potato cell clock. The googly eyes were done in Photoshop (but I want to get some real ones for when I use this on class). Designed with @tinkercad and 3d printed in PLA.

[Alfredo Mateus 🧪⌬ @alfmateus]

@MrShortFHS_sci the first is a polyurethane foam kit (with food coloring). Second is good old PVA slime. Third is a demo I created using a PET bottle (https://t.co/AYLCyJDoPH). The last one is dissolving styrofoam w/ limonene (instead of acetone) and starch w/ water.

[Alfredo Mateus 🧪⌬ @alfmateus]

Today the students explored several polymer experiments... Do you know them all?

[Alfredo Mateus 🧪⌬ @alfmateus]

Yesterday the students did a rotation that included the salt + ice + wet thread experiment. Always good when there's a surprise in the end.

[Alfredo Mateus 🧪⌬ @alfmateus]

Have you ever done the evaporation races? 2 liquids compete and the sts discuss the intermolecular interactions and their relative intensities. I've made this board using laser cut MDF. You wet cotton balls with each liquid and make a trace. Water x ethanol x i-propanol x acetone

[Alfredo Mateus 🧪⌬ @alfmateus]

@KatyDornbos I'd expect a difference related to the number of particles released when the salt dissolves. Sodium carbonate (3 particles) should be better than sodium chloride (2). But I'd not expect a change based in cation used. You use the same mass of each salt? Or moles?

[Alfredo Mateus 🧪⌬ @alfmateus]

@CummingsLinda @ChemEdX no, it is not the link.

[Alfredo Mateus 🧪⌬ @alfmateus]

@hankgreen You will certainly not fix the housing problem with houses. But american cities don't let people build large, tall apartment buildings anywhere. Huge houses everywhere, for just one family.

[Alfredo Mateus 🧪⌬ @alfmateus]

I am in London for a few days. Today I went to the natural history museum, a lovely building (if a bit cold) and a very nice collection. I plan to visit the Royal Institution and the Faraday museum tomorrow.