Sunday, September 18, 2011

Epsom Salts - Let's Get Physical (and Chemical... Properties)!

Physical Properties 
Each of the following properties listed are physical properties because I did not change the chemical ID of the substance to discover the facts.

Color
To begin, I decided I would try to determine the color of said Epsom Salts. It was quite the difficult task. It involved opening the carton and looking at it. Very tough. But after careful consideration that looked a lot like this:

I realized that epsom salt was, in fact, white. It also did have a transparent quality as well. Neat-o. 

Phase
Next, I needed to discern the phase of the salt. After centuries of this:

I came to the conclusion that it was a solid (as it was defined by having both a definitive shape and volume).

Malleable
Malleability is the ability to be hammered into thin sheets. So naturally I picked this property to try because it sounded like fun. This is what it looked like (be afraid):

But much to my dismay (and my mother's delight), epsom salt is not malleable. It just broke down into smaller grains, like so:

Bummer. So it's safe to say that malleability is not a physical property of epsom salt.

Solubility
AH! One of my favorites. I put about a half cup of the salt into about a half cup of water. Interestingly enough, the result was this:

As we can see, after stirring the mixture, it separated. Upon closer inspection, we can see that the crystals have lost their milky hue (which is now tainting the water). The compound that is epsom salts (magnesium sulfate) does not completely dissolve in water. In a later property, I shall explain what has happened.

Taste
Oh, God. This one was NASTY. Every tried tasting magnesium sulfate? I do NOT recommend it. So after letting one crystal dissolve on my tongue and was disgusted, I delegated the task:
The Original Chemistry Cat

She was not impressed. The salt had a bitter taste. It was gross. But I digress. I just need to communicate how positively revolting it was. 


Chemical Properties
Each of the following properties listed are chemical properties because I did have to change the chemical ID of the substance to discover the facts.

Flammability
One of my personal favorites. This required safety goggles and adult supervision (two of my least favorite things... the sacrifices I make for science). I dumped a pile of the salt on the ground and stuck a match. It was just as neanderthal as it sounds, and it looked like this:
Pretty Snazzy, no?

Despite the annoying wind that kept blowing out the flame, I managed to block it for long enough to know that no amount of prodding will end in a bonfire. Disappointed, I blew out the match and shuffled back inside, where I discovered five mosquito bites. Not only did I not get the explosion of inferno that I dreamed of, I had to set back my schedule to treat my wounds. Epsom salt is not flammable... darn.

Reactivity of Acid
At the request of our teacher, we were not allowed to break open a battery and pour it on the substance. But I made do with vinegar. So I put a half cup of epsom salt in a cup and poured in enough vinegar to drown a bat. Again, no furious explosion, nothing. Sad, really. It just did this:
Big, Fat, NOTHING!

So it is safe to say that epsom salt does NOT react with acid. So what does it do? Which brings me to...

The pH Balance
Not exactly the most exciting, but whatever. Since I didn't have any means to conduct this test on my own, I used the magical world wide web. According to W Chemicals Online (http://w-chemicals.com/properties-of-magnesium-sulfate/) the pH balance of magnesium sulfate is 6.0. Neither an acid or a base, right in the middle. The pH balance of a solution is the measure of how much hydrogen is in a given substance. In order to gain this information, we must change the chemical ID of the substance, thus it is a chemical property.

Upon Heating
According to W Chemicals Online (http://w-chemicals.com/properties-of-magnesium-sulfate/), when magnesium sulfate is heated at over 250 degrees Celsius, epsom salt is broken down into magnesium oxide. Which changes the chemical ID of the substance. Which makes it a chemical property. TADAA!

Transfer of Energy
In my personal opinion, this is the coolest. First, I put a half cup of lukewarm water in a jar. My dad happened to have a temperature probe. The water was 26.6 degrees Celsius.

After, I added a half cup of epsom salt. I stirred it until the water had broken the substance down into two ions: magnesium and sulfate (thus changing the chemical ID). The energy it took to make this change lowered the temperature. The second measurement of heat (after the salt was added) was 22.2 degrees Celsius. This was an endothermic reaction. Cool, no?

This concludes today's chemistry lesson. Thank you and good night.









10 comments:

  1. Very impressive! I've got to say, there were some very creative ideas presented in this blog post. You also incorporated a dash of humor, which is clever. I find all of your arguments to be quite sound, but one is sort of bugging me. Under physical properties, you listed TASTE. However, in order to taste something, saliva and other enzymes in the mouth react with the compound, making it accessible to the taste buds. Therefore, taste couldn't happen without a chemical reaction. Therefore, I think that taste should be under chemical properties, not physical properties. Good job on the whole though!
    PS: I plan on commenting on your blog for the rest of the year :)

    ReplyDelete
  2. Thanks for the input!
    But look a the first page on:
    http://www.utm.edu/departments/cece/cesme/psam/PSAM/psam11.pdf.
    As you can clearly see, taste is, in fact, a physical property. Although taste is a chemical sense, you do not need to change the chemical ID of the substance to be able to investigate this quality.
    That said, I can see how it could go both ways.
    Regardless, I look forward to your commentary.

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  3. Although your UT evidence is rather persuasive, Linus Pauling begs to differ. As Wikipedia explains, Linus Pauling "was one of the most influential chemists in history and ranks among the most important scientists of the 20th century. Pauling was among the first scientists to work in the fields of quantum chemistry and molecular biology." In his book, he takes my side: http://books.google.com/books?id=EpxSzteNvMYC&pg=PA12&lpg=PA12&dq=taste+chemical+property&source=bl&ots=PINDqkA-OZ&sig=pXcp3PcseORO72ATAIo06f2doc4&hl=en&ei=vVl6TrD1Ac_FsQKJwunNAw&sa=X&oi=book_result&ct=result&resnum=6&ved=0CFcQ6AEwBQ#v=onepage&q=taste%20chemical%20property&f=false
    Take a look at page 12

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  4. While Mr. Pauling makes a good point, his book is outdated. The first copyright is 1947. This would not be a problem, but he said "There is still complete lack of knowledge as to the way in which the molecules of tasty and odorous substances interact with the nerve endings in the mouth". Since this has been published, taste as a property has been re-evaluated. We could have this argument forever, Cyrus. And while I do appreciate your critiques, there is no way to come to a consensus. Taste could go either way. It depends on your source and your definitions. I've enjoyed our little debate. Goodbye.

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  5. Alright, just notify when the next blog post goes up!

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  6. This post had me "rolling on the floor laughing", as teenagers these days put it. This quality kept me wanting to read, which is quite impressive when it comes to educational articles. HOWEVER, I would like to point out that in physical properties, when you tried to find out whether epsom salt was soluble or not, you did a great job at explaining what HAPPENED to the salt, but not whether or not in the end it was indeed soluble. I need closure, Cara. Closure. Also, you misspelled "struck" when talking about your match adventures. Overall, very, VERY good post, even if it did have cats in it!
    -Jasmine

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  7. Well Cara, you did a pretty amazing job as usual. I "ROFL'ed" a little bit as well as Jasmine said. I never really thought much about epsom salt and I really liked learning all of these interesting physical and chemical properties about it. We don't have Mrs. Gende anymore, quit trying to impress her with the cats hahaha! My favorite was the endothermic reaction as well. Its crazy that two little things mixed together make such an interesting reaction. Overall, great job! (still ROFL'ing)
    -Much love, much love… Ford

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  8. Cara, you did a great job. The many jokes and pictures kept me reading. Epsom salt never struck me as interesting, but this report was really amazing. The endothermic reaction that took place was truly COOL. Get it? Because the temperature went down...I crack myself up. Nice lab overall.
    -Brandt Ging Wood

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  9. Great job Cara!! I would have never thought to experiment on epsom salt! I loved the pictures you put with it and how you make it more of a fun blog, and not strictly matter of fact. it made it much more interesting to read!
    Caroline Mitchell (the other ginger)

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  10. IM SO CUNFUZED! WHAY IZ YER EYE SUH BEEG IN DEH FUST PICTCHA!?

    ReplyDelete