A Little Something To Ponder…

“If I have seen further it is only by standing on the shoulders of giants.”

Isaac Newton

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Mole Day — An Explanation

Happy Mole Day!

For many of you, it’s likely you have no idea what a mole is. Sure you know of a mole as a raised piece of skin that’s darker than the surrounding area. You also know a mole as a small underground-dwelling insectivore. It’s possible you even know a mole is a type of spy. There’s even the kind of mole that you put on your food, but that’s pronounced differently. “Mole-ay” sauce, as it’s pronounced, is a dark-red/brown chili-based sauce used in Mexican dishes.

But there’s also the mole used in science. A mole, whose unit is simply mol (mole : mol :: kilogram : kg :: meter : m), is a unit of measure used almost exclusively in chemistry.

A mole (mol) is an amount of substance that contains as many particles* as there are atoms in exactly 12 grams of carbon-12.

*By particles, I mean atoms in a sample (such as C) or molecules in a sample (such as H2O).

So 1 mole of carbon has the same number of “particles” as 1 mole of anything else, be it water, sodium, or gold.

Now what is that number? The short answer is, it isn’t important. lol

The slightly longer answer is 6.02 x 10^23, which is called Avogadro’s number. Yes, it’s a HUGE number.

So if you have 1 mole of Carbon (pure carbon 12), it will weigh exactly 12 grams and will have 6.02 x 10^23 number of carbon atoms in it.

If you had a mole of water, it would have the same number of H2O molecules, but would weigh 18 grams (16 grams for the oxygens and 2 x 1 grams for the hydrogens).

So just as a dozen diamonds (made of carbon) would weigh a different amount as a dozen gallons of water, so does a mol of carbon weigh a different amount than a mol of water!

If at this point, you’ve missed what mole day could be celebrating, I will tell you that today is October 23rd. Otherwise known as 10/23, a magical part of Avogadro’s number. ūüôā So scientists and numerologists unite! And at 6:02 am and pm, particularly, celebrate.

But AmoebaMike, what else do I need to know about taxonomy and evolution?

In order to standardize names of organisms, back in the the 1700s, a Swedish botanist named Carl Linnaeus developed a two-name system. Referred to as, binomial nomenclature, it is the system with which we use–even still today–for naming organisms.

Carl von Linné, Alexander Roslin, 1775.
Scientific Hottie
Carl Linneaus,
Image via Wikipedia

The word binomial means “two names.” So it is by using two names that we fully name each organism, in the same way that you have both a first and a last name. In binomial nomenclature, the first of the two names indicates the genus name. A genus is a group of closely related species. The second name is the species name; often it is a Latinized version of a word that describes a trait of the species, a location where the species can be found, or even an influential person in the discovery or science of that particular species. See the accompanying image.

Click for full size

Finally, you need to know how organisms are classified. Scientists try to make maps, or trees, called cladograms to show the relationship between different species. It used to be that organisms that were organized in cladograms based on physical similarities the species shared with one another. For example, as the name implies, the horseshoe crab looks like a crab. ¬†In fact, it’s actually more related to spiders than it is to crabs!

Now that science has advanced greatly in the past half-century or so, cladograms are built using information scientists gather from DNA and RNA sequencing. ¬†We’re finding out that like the horseshoe crab, some things we thought were related aren’t really all that close! ¬†Have you ever heard of a panda or a koala being referred to as panda bear or koala bear?

Bears are members of the family Ursidae. ¬†The bears you think of when you hear the term “bear”, like the grizzly bear and the polar bear are in genus Ursus. ¬†Ursus is one of the genera of family Ursidae. Pandas are members of family Ursidae, but their genus is Ailuropoda. So they’re technically bears!

Koalas share the same class as the bears, Mammalia. ¬†That’s as close as they’re related. ¬†Koalas aren’t bears any more than dogs or whales are bears.

One last note: as you see in the image, the proper way to discuss a species is using the full name and italicizing it. The genus name gets capitalized, but can also be abbreviated by the first initial. For example, koalas would be Phascolarctos cinereus or P. cinereus and pandas would be Ailuropoda melanoleuca or A. melanoleuca.

In which I meet Bill Nye The Science Guy

Bill Nye the Science Guy

Science Cards – Two Great Women

After a slew of business trips and a broken piece of software, I’ve finally got the latest–and last*???–science cards for you!

First up is Marie Curie, the first person honored with two Nobel Prizes!  Best known for her work as a pioneer in radioactivity, Curie had a distinguished career that included isolating radioactive isotopes, discovering two chemical elements (she even had one named after her!) and working to cure cancer with radiation. Continue reading

Science Cards – No Catchy Subtitle This Time

I spent 8 out of 9 days on the road since the last time I posted a science card. ¬†So you’ll have to give me a bit of a break on the lack of a catchy subtitle. ¬†Feel free to come up with one of your own and make me feel bad for how easy it was for you to think of.

(If this is your first experience with my science cards, here’s the brief synopsis: cards that include a “legend” are made up by me. ¬†In most cases, the current scientists are providing their own info to me. ¬†When reading a star rating, 1 star is indicative of the level in which normal mortals reside.) Continue reading

Science Cards – The Hermit & The Hottie

While the other big name reputable science bloggers are writing about poop today, I present a new pair of science cards.

Actually one of the most famous people in the world at one point, our first scientist had hermit tendencies–especially later in life. [src]¬† ¬†Nikola Tesla didn’t invent electricity–that was nature–but he certainly found new ways to use it. An engineer, physicist, and prolific inventor, Tesla has his name on a unit of measure, museum, currency, car–just about everything short of a pair of Nike! Continue reading

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