August 19, 2016

Coating to make soap pour cleanly out of plastic bottles, reduce waste and frustration



Anything that makes recylcing easier is to be lauded.

In this article from phys.org, Ohio State researchers found a way to spray coat polypropylene and polycarbonate with
a small amount of solvent and ultra-fine silica nanoparticles onto the inside of bottles. Manufacturers already use solvents to change the texture of molded plastics, because they cause the surface of the plastic to soften a little. By mixing the silica and solvent, the researchers were able to soften the surface of the polypropylene just enough that when the plastic re-hardened, the silica would be embedded in the surface. 
The structures are only a few micrometers—millionths of a meter—high, and covered in even smaller branchlike projections. They look like shaggy heart-shaped pillows, but they're hard as glass. 
They don't cover the inside of the bottle completely, either, but instead are planted a few micrometers apart. The main branches of the "y" overhang the plastic surface at an angle less than 90 degrees—steep enough that water, oils and even surfactant can't physically sustain a droplet shape that would fall in between the branches and touch the plastic. 
"You end up with air pockets underneath, and that's what gives you liquid repellency," Brown said.  
Instead of spreading out on the surface, the soap droplets form beads and roll right off.

Gïk Live! - ¿Cómo se produce el vino azul?



I was reading Uproxx, as I am wont to do, and came upon an article about blue wine. In the article was the following sentence...
To get its distinctive color (self described as “Indigo Blue, WTF.”) the folks at Gik blend red grapes, white grapes, and chemistry.
Well, if they've included chemistry, then it has to be good.

I went hunting a little bit and am pretty sure that they're using the basics of anthocyanins to adjust the color of the wine. All they would have to do is take the pH of the wine from something in the 4-6 range to something in the 7-8 range. Wouldn't be all that tough, I would think.

Luckily one of their own videos says as much...



Aren't pH indicators great?

Gïk Live! - ¿Cómo se produce el vino azul?



I was reading Uproxx, as I am wont to do, and came upon an article about blue wine. In the article was the following sentence...
To get its distinctive color (self described as “Indigo Blue, WTF.”) the folks at Gik blend red grapes, white grapes, and chemistry.
Well, if they've included chemistry, then it has to be good.

I went hunting a little bit and am pretty sure that they're using the basics of anthocyanins to adjust the color of the wine. All they would have to do is take the pH of the wine from something in the 4-6 range to something in the 7-8 range. Wouldn't be all that tough, I would think.

Luckily one of their own videos says as much...


Aren't pH indicators great?

Dogs Teaching Chemistry



How frickin' cute is that, huh?

I know the dogs aren't exactly staying in place for the entire video. The cuts aren't all that smooth.

Still, though, the dogs are so marvelously well trained - holding the ball and rope evenly, unevenly, tugging on command. It's brilliant.

Let's see if the dogs know about atoms.



Huh, apparently they do.

June 24, 2016

HOLDING AN EXPLOSION at 20,000 fps - Smarter Every Day 156



That's brilliant.

The explosion there is wonderful and marvelous to watch. Gorgeous stuff, there.

Seriously, the explanation of the combustion and the slow-motion imagery is spectacular.

In the daytime, it's a little less thrilling.

June 19, 2016

See, because oxidizing..


Totally true unless your car is made out of iridium.

Source - XKCD

Trader Joe's Alkaline Water


So, Trader Joe's is selling alkaline water.

You know, just in case you need that stuff.

I happened to be over at the TJ's recently and took a photo of the back of the bottle to see what ingredients were that made it alkaline.


Potassium carbonate, potassium bicarbonate, and magnesium sulfate...simple enough then.

In AP chemistry we discuss the pH of salt solutions, and the first two of those salts are pretty straight forward.

K+1 + H2O --> KOH + OH-1

Not gonna happen because that would involve the creation of a strong base solution (KOH) something that isn't feasible.

The anions, however, do react with the water to form alkaline (basic) solutions.

CO3-2 + H2O <--> HCO3-1 + OH-1

HCO3-1 + H2O <--> H2CO3 + OH-1

They would, indeed, make alkaline solutions because they're remaking weak acids.

The third salt, magnesium sulfate, is a little more complicated as both ions form weak acid/base solutions. There the Ka and Kb values have to be considered.

Mg+2 + 2 H2O <--> Mg(OH)2 + 2 H+1

SO4-2 + H2O <--> HSO4-1 + OH-1

The water, then, is definitely alkaline/basic. Is there, however, any advantage to drinking alkaline water? That's a different question entirely.

At this point, I'm certainly skeptical on the values of drinking alkaline water based on my brief bit of research. The folks who promote alkaline water seem to fit a lot of characteristics of snake oil salesmen.

I will be using the alkaline water in AP chemistry next year, however, and asking the students to explain the pH effects of the dissolved salts.