Monthly Archives: October 2017

Ow Ow Ow Ow Ow!

A storm in Rio Negrinho, in the North of Santa Catarina, Brazil, brought down a good number of trees. One of those trees came right down on a Volkswagen Kombi, smacking it right in the middle, the result looking like what would happen if you dropped a small barbell onto a loaf of bread.

Mole Day

October 23rd is Mole Day—you know, because 10/23 is like 1023.

THE EARLY HISTORY of chemistry has many interesting stories. Just consider the problems scientists had 200 years ago as they tried to figure out some of the most basic ideas of chemistry. It was clear that there were different substances—for instance, water is different than coal. But it wasn’t so clear what these substances were made of. You could take something like nitrogen gas (N2) and oxygen gas (O2) and combine them together to make another gas (in this case NO2). It thus seemed reasonable to suppose that stuff (molecular gas) was made of smaller stuff (atoms). But the evidence isn’t so easy to see. The primary difficulty is that humans can’t see molecules or atoms. All the scientific ideas have to be built on indirect evidence.

This is where Amedeo Avogadro comes into the picture (of course his real name is Lorenzo Romano Amedeo Carlo Avogadro di Quaregna e di Cerreto—but everyone just calls him Avogadro for obvious reasons). Avogadro developed the following idea:

Avogadro’s Law: If you have two gasses at the same temperature and pressure, they will occupy the same volume only if they contain the same number of molecules.

If you are thinking this is just a version of the Ideal Gas Law, you are correct—but let’s move on to a useful example. Suppose you take water (which is H2O) and run an electric curent through it—called electrolysis. This can break the water molecules into hydrogen gas and oxygen gas (which you could collect). If you had these two gases at the same temperature and pressure, the hydrogen gas would take up twice the volume compared to the oxygen gas. Why? Well, when you break up the water molecule, you get twice as much hydrogen as oxygen. Yes, hydrogen doesn’t just float around as a single atom. Instead it forms a bond with another hydrogen to make H2—but oxygen does the same thing (O2).

In the end, you would know that water is made of both hydrogen and oxygen and that there is twice as much hydrogen as oxygen. That’s a pretty big piece to the whole elements puzzle and you need an idea like Avogadro’s Law to figure it out.

Avogadro’s Number

But what about this number of Avogadro? Why is it important and why didn’t Amedeo know what it was? Let’s start with a definition. If I have 12 grams of carbon-12 (not any other isotopes of carbon) then it would have exactly Avogadro’s number of atoms in it. We can write this number as (approximately):


So we would call this number of carbon atoms, one mole (sort of like 12 eggs is one dozen).

Why is important? Avogadro’s number is sort of like a bridge. It bridges chemistry and atomic physics. In chemistry we measure things based on their bulk properties. Things like mass (total mass), pressure, volume, temperature. However, when we consider these things from an atomic perspective we look at individual atoms and the momentum, velocity of these particles. Avogadro’s number connects these two ideas and allows us to explore atomic-level things by measuring macroscopic level quantities. It’s a big deal.

But why didn’t Avogadro know this number? Because he didn’t directly come up with the idea. Chemists named the number after Avogadro to honor his contributions to chemistry.

Determining a Value for Avogadro’s Number

If you had a carton with a dozen eggs, you could open up the package and count the number of eggs to find out that one dozen equals twelve. You can’t really do the same thing with a mole of carbon. Carbon atoms are too tiny to see and there are too many to count. We have to find another way to get a value for Avogadro’s number. There are quite a few ways to determine this magic number, but let me go over a simple method.

Start with two pieces of copper placed in a solution of copper-sulfate. When you run an electric current through the system, copper is removed from one plate and deposited on the other plate. This means that one of the plates gains mass and the other loses mass (should be by the same amount).

When the copper atom is removed from one plate, it acts as a charge carrier in the complete circuit (battery, wires, copper, solution). If I measure the current in this circuit and record the time, I can use the definition of current to find the total transfer of charge (which would be the transfer of copper ions).


Let’s put this all together.

  • Run current through the copper and copper sulfate.
  • Positive copper ions are transferred from one plate to the other making a change in mass (which I can measure).
  • I can measure the current and time and calculate the total transfer of charge from one plate to another.
  • Since a copper ion has a positive charge of 1 e (charge of an electron), I can get the number of ions transferred.
  • Knowing that 1 mole of copper is 63.546 grams, I should be able to get a relationship between the change in mass and the number of moles—which will give me Avogadro’s number.

In my rough experiment, I had an electric current of 0.42 Amps for 10 minutes. This gives a total change in charge of 252 Coulombs. Dividing this by the charge of one ion (1.6 x 10-19 C) I get 5.575 x 1021 ions. The change in mass of one plate is 0.344 grams. That’s all I need. Now I can write:


That’s not a terrible value for Avogadro’s number. Really, it’s not. If you take the accepted value of 6.022 x 1023, then my estimate is just off by less than a factor of 2. I call that close enough. The idea works even if my method was a little bit sloppy. Still, my value is better than no value.

How to Avoid a Rotten Jack-O’-Lantern

Your jack-o’-lantern looks so good, bright and orange next to your front door, harbinger of the season, home to a flickering tea light at night. Or does it? Has it started, maybe, to shrivel and shrink? Is it perhaps a tiny bit stinky? Even if it’s still looking good, what assurance do you have that it will make it to Halloween?

Whether you carved a pumpkin a week ago or are only just getting your knives out now, there’s plenty you can do to prevent them from rotting, according to Apartment Therapy.

First, if you haven’t carved your pumpkin or aren’t going to, give that baby a bleach bath. Find a tub or bucket big enough to hold your pumpkin, and mix one to two tablespoons of bleach for each gallon of water. Dunk that pump’  and soak it for ten minutes. If you’re going to carve, let the pumpkin dry completely first.

To protect an already-carved pumpkin, make a bleach spray (with the same proportions) and use it on the outside and carved surfaces of your pumpkin. (Let it dry upside-down so bleach water doesn’t pool inside.) Re-spray every few days.

Once all that’s done, keep in mind how the weather affects a carved gourd sitting outside. Place your pumpkin where it’s shielded from rain, and if temperatures are dropping toward freezing, bring the guy inside overnight. Freezing water expands and can burst the walls of plant cells. Burst cell walls mean mush, and mush is the last thing you want your jack-o’-lantern to be.

Cat Diary

Dog Diary


The Last Holden Has Been Built In Australia

It’s a sad day for those of us who liked knowing that there was a company building big, V8-powered beasts, just like here in America, down at the bottom of the Earth. The company was GM’s Australian subsidiary Holden, and today they finished their very last car.

Read more »

Mythbusters 2.0?

What do you do when your highly-successful reality show goes out with a bang? If you’re Discovery-owned Science Channel, you quickly reboot it and find new hosts to replace the iconic ones. If you’re a fan of the original and willing to give the new guys a chance to prove themselves to be as awesome as Adam and Jamie are, then you’re in luck. The new version of Mythbusters, a much-loved show that reveled in DIY gadgetry and science, is set to air its first of 14 episodes on November 15th.

Yup, that’s my tail!

Yup, that’s my tail!

150th Anniversary of the Alaska Purchase

On this day in 1867, the U.S. formally takes possession of Alaska after purchasing the territory from Russia for $7.2 million, or less than two cents an acre. The Alaska purchase comprised 586,412 square miles, about twice the size of Texas


LEGO Lawn Mower Man

Vampire Bat

Top Halloween Candy by State

See the interactive map, and the rest of the story, here.


Micrathena sagittata

National Geographic Explorer Jonathan Kolby was in the jungle in Honduras researching amphibians when he spotted a spider with a spectacular rear end. The spider (Micrathena sagittata) is red, except for an abdomen that resembles the head of the Pokémon character Pikachu. It’s not a rare species, just tiny and hard to spot even if you’re looking for them. But why the coloring that acts like a safety vest? A 2002 experiment on similarly colored spider in Australia hints that standing out actually attracts prey.  

Using a black marker, the researchers “erased” the spiders’ bright yellow color. The spiders whose colors had been thus muted were on average less successful at catching prey. Like arrow-shaped micrathenas, the Australian spiders are “sit-and-wait” predators that ensnare prey in large webs.

Maybe when insects see this, they don’t think “Pikachu” as much as they think “flower.” Read more about the PIkachu spider at National Geographic News. 

Mystery Oreo

This Canadian Lake Hides an Underwater Ghost Town

Lake Minnewanka in Alberta was once home to a bustling resort, but today its eerie landscape can only be seen by scuba divers

Read more here.

14 Of The Most Expensive Cats In The World

  • 1

    Norwegian Forest Cat, up to $3,000


    This fluffball’s ancestors were bred by Vikings over 2,000 years ago, with lush fur to  keep them cozy in cold forests and awesome hunting skills.

  • 2

    Himalayan cat, up to $1,300.


    Although it looks a little like a Persian cat, the blue eyes and colorpoint coloring is characteristic of a Himalayan. Bred in the US in the 1950s, these cats are friendly, calm and obedient.

  • 3

    Scottish Fold, up to $1,500.


    Scottish Folds have the cutest ears of all cats which, as the name suggests, look like they’ve folded over, the result of a genetic mutation. These clever cats are very sociable and playful, and they’re known for standing on their hind legs to watch the world go by.

  • 4

    Peterbald, up to $1,200


    Also known as the Petersburg Sphynix, this cat was first bred in Russia in 1994. They can be bald of fuzzy, and they’re sociable and calm in nature and very easy to train.

  • 5

    Egyptian Mau, up to $1,500.


    They’ve been around since Ancient Egypt, but they haven’t changed much in 3,000 years. As well as their fur, these cats actually have spotted skin.

  • 6

    Maine Coon, up to $1,500


    This super-size cat is more like a small lion than a house pet, reaching up to 1.23m in length. But they’re affectionate and playful, despite their giant size.

  • 7

    La Perm, up to $2,000


    Bred in the 1980s in the US, these cats have distinctive curly fur (like a perm, geddit?) and they’re hypoallergenic, so even people allergic to kitties can cuddle up with these fluffy pets.

  • 8

    Russian Blue, up to $2,000


    These kitties originated in Russia in 1893, and are a very popular shorthair breed, possibly because they’re said to bring luck the the house they live in.

  • 9

    Elf cat, up to $2,000


    This young breed was only developed in the US in 2006. Elfs are said to be friendly, smart, mischievous, curious and devoted — even if they look a bit weird.

  • 10

    American Curl, up to $3,000


    This California-bred cat remains small — it’s hard to tell a kitten from a full-grown adult — and when they’re around 10 days old their ears begin to turn back, like tiny little horns.

  • 11

    Khao Manee, up to $11,000


    First mentioned in the “Cat Book Poems” of ancient Siam in 1350, these were the favored cats of royalty and considered a symbol of luck, longevity, and wealth (which you’d need anyway to afford one).

  • 12

    Caracal, up to $10,000


    Technically a wild cat, this breed is in danger of extinction and kitty-lovers are encouraged to buy them to preserve their species, making them a favorite for wealthy people looking for exotic pets.

  • 13

    Savannah cat, up to $22,000


    Bred from an African Serval and a domestic cat, this leopard for your home can grow up to 33lbs and reach 1.9ft in height. They’re super clever and super active, needing lots of space to play and long walks

  • 14

    Ashera, up to $100,000


    The most exotic domestic cat in the world (and the rarest), the Ashera is a cross between a domestic cat and an Asian leopard. Stunningly beautiful — if you’ve got a spare $100,000 lying around.

Large case of NOPE right here!

YouTuber Cargospotter brings us a look at an Airbus A380 touching down in Germany’s Düsseldorf airport. The crosswind was blowing hard that day, so hard it nearly blew the plane off course.

Wara Art Festival 2017 Time-Lapse

The Wara Art Festival in Japan’s Niigata Prefecture is a showcase for art, but it’s also a harvest festival. Giant sculptures are constructed of rice straw leftover for this year’s rice harvest.

The Wara Art Festival all started in 2006 when the local district reached out to Musashino Art University to seek guidance on transforming their abundant amount of rice straw into art. And in 2008, the very first Wara Art Festival was held. Since then, every year the school sends art students up to Niigata to assist in creating sculptures made out of rice straw. The festivities have ended but the sculptures are on display through October 31, 2017.

In this video, watch students from Musashino Art University build one of the sculptures for 2017.