XKCD 3094 - Mass Spec

 

Source - XKCD

See, it's funny because this is a very rudimentary version of a mass spectrometer.

The person is the aerosolized sample atom which is ionized via balloon charging, accelerated by running and jumping, deflected via the magnet, and detected by position on the target on the wall.

It's almost exactly how mass spectrometry works...only ridiculously so.

Student Submitted - Hund's Rail

Source - C&EN

Today's post was submitted by Katelynn J, one of my AP chemistry students. As a sub assignment after the AP chemistry exam, I had students submit two posts for this blog. I'll be posting them over the next few weeks.

During COVID-19, this cartoon was probably especially relatable, since everyone was trying to stay as far away from each other as possible. Of course, staying healthy and safe is much more important than adhering to the buddy system, but when going into two separate cars, you’re sure to miss your travel companion at least a little.

In this specific comic, however, the problem isn’t social distancing, it’s Hund’s Rule. On the rail, representing the shells of the QMM, electrons after first fill up all empty spaces before being able to double up, since this stabilizes the atom. The two electrons here trying to enter a car together would make the atom unstable, so it’s better they stay apart.

Katelynn added that "I learned that Hund has more than one rule! His rules are best for the ground state of an atom, and all three have to do with electrons," and she found this website helpful for further reading.

Student Submitted - The chemistry of papal smoke

Today's post was submitted by Katelynn J, one of my AP chemistry students. As a sub assignment after the AP chemistry exam, I had students submit two posts for this blog. I'll be posting them over the next few weeks.

Following the death of Pope Francis, a new pope now needs to be chosen. 16-20 days after the mourning period for Francis, elections have now begun and ended, and cardinal Robert Prevost, now Pope Leo XIV, has been chosen. During this selection period, all cardinals under the age of 80 travel to the Vatican to vote, and they are isolated from society until a decision is made. In order to keep the outside world updated, after every vote, ballots are burned and either black {indicating no decision has been made} or white {indicating a pope has been elected} smoke “billows” from the chimney of the Sistine Chapel. Interestingly, the longest conclave took 3 years, following the death of Pope Clement IV in 1268.

But fire only produces one color of smoke, normally. So how are the two colors created? Originally, white smoke was made by the burning of the ballots and the addition of dry grass for a lighter smoke color, and black smoke was made by ballots, wet straw, and rosin to darken the smoke. In modern times (after 2005), a mix of chemicals are used for each color. Chemicals listed here.

This chemical cocktail works because of the state of matter changes that occur. When a substance, like the chemicals used, is vaporized (fire does that!), the particles will recondense in the air, blocking light and only allowing some colors through, the color of smoke that we see.

Learn more about how other non-white/black colors of smoke are made at this link.

Student Submitted - Fruit browning

Today's post was submitted by Aleeyah B, one of my AP chemistry students. As a sub assignment after the AP chemistry exam, I had students submit two posts for this blog. I'll be posting them over the next few weeks.

You know when you cut a piece of fruit and it turns brown after a while, or a banana peel? This article explains how to stop this from happening. This is actually because of a chemical reaction called oxidation. Fruits contain an enzyme called polyphenol oxidase, also called PPO. When the fruit is completely intact, everything stays inside the peel. However, if the fruit is bruised or cut, oxygen in the air goes into the fruit. The enzyme I mentioned before, PPO, reacts with oxygen and turns into something called melanins. This causes the browning we see. This process is called enzymatic oxidation. So the article just explains ways to slow this oxidation reaction.

I found it interesting that fruits turning brown does not necessarily mean that it is going bad. I always viewed brown fruits as spoiled, but now I might view that differently.

Learn more about fruit browning at this link.

Student submitted - Saponification

Today's post was submitted by Aleeyah B, one of my AP chemistry students. As a sub assignment after the AP chemistry exam, I had students submit two posts for this blog. I'll be posting them over the next few weeks.

We use soap every day, I hope, but we rarely stop to think about the chemistry of it. This source tells us that soap is made when a fat or oil made of triglycerides (fat found in blood) reacts with a strong base such as sodium hydroxide. This reaction breaks down the triglyceride molecules and makes something called glycerol (a sugar alcohol) and what we call soap. Every soap molecule has two ends, one hydrophilic and one hydrophobic. The hydrophobic end attracts to the oil and grease (non-polar), while the hydrophilic side attracts to the water (polar). As we wash our hands, the soap is able to grab the oil, but is also able to be washed away by the water.

Something that I thought was funny was that soap doesn’t just murder all the germs on your hands, but actually washes them away. I always thought soap instantly killed any bacteria it touched, and not necessarily washed them away.

You can learn more about saponification at this link.

Glittering war zone halos named for fallen heroes

Stick with me, folks.

I wouldn't normally turn to Fox News for my science reporting, but their story does the best job - of the ones I quickly searched on YouTube - of explaining the Kopp-Etchells effect in which the edges of helicopter rotor blades get abraded via airborn grains of sand, sending showers of pyrophoric tittanium-nickel alloys into the air and making for a lovely light show - that admittedly shortens the lifespan of the blades and advertises the presence of the helicopters at night.

Effectively, it turns the edges of the blades into sparklers.

It makes for some really pretty pictures, though...

Source - reddit

Source - wikipedia

Here's another video with a little more science presented in meme-ified format.