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What is an easier way to memorize the chemical formula of Nitro Glycerin (C3H6N3O9)?
What is an easier way to memorize the chemical formula of Nitro Glycerin (C3H6N3O9)
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Robert Rossi
Many things! But mostly chemistry and chemical engineering
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Robert’s Answer
If you are trying to remember the chemical formula of an organic molecule, being able to decipher the parts of the name can be a big help. An organic chemist would decipher "nitroglycerin" into two parts: "nitro" and "glycerin." Glycerin is a simple triol, meaning it contains three alcohol (-OH) groups, each connected to a different carbon atom. In the case of glycerin, that's pretty much all there is to the molecule: three carbon atoms, each with an -OH group on it, and H atoms everywhere else, with the carbon atoms connected in a straight chain (rather than a ring, and with no double bonds): CH2OH-CHOH-CH2OH. (That this is "glycerin" you pretty much have to memorize.) To get nitroglycerin, the each hydrogen on an alcohol (-OH) group is converted to a nitro (-NO2) group: CH2ONO2-CHONO2-CH2ONO2. Adding all the atoms up gives you the formula, C3H5N3O9. This may not, on the face of it, seem easier than just memorizing C3H5N3O9, but "nitro" and "glycerin" will come up in many other cases, so knowing those two names is far more valuable than memorizing the formula of nitroglycerin itself.
Randall Detra
Industry: Environmental testing/research. Academic: chemistry, biology, physical science
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Randall’s Answer
You could consider drawing the structure on a piece of scrape paper. I would like to show you an example but need to use words here:
1. three connected carbons
2. three Oxygens one connected to each carbon
3. three Nitrogens, one to each Oxygen
4. two oxygens, a pair connected to each Nitrogen
5. Finally you need to round out the three carbons with hydrogens to make the requisite four bonds.
When you do this you can count them all up if you need to. They are C3H5O9N3.
My goodness! there are only five hydrogens in nitroglycerin, not six! As long as you remembered the four bond rule for carbon you just learned nitroglycerin has 5 hydrogens instead of 6!
1. three connected carbons
2. three Oxygens one connected to each carbon
3. three Nitrogens, one to each Oxygen
4. two oxygens, a pair connected to each Nitrogen
5. Finally you need to round out the three carbons with hydrogens to make the requisite four bonds.
When you do this you can count them all up if you need to. They are C3H5O9N3.
My goodness! there are only five hydrogens in nitroglycerin, not six! As long as you remembered the four bond rule for carbon you just learned nitroglycerin has 5 hydrogens instead of 6!
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Melody’s Answer
Hello Jonathan,
Consider using a mnemonic device, like this one: "Three cats hunted six nitro-catnips across the three vast oceans in November." Alternatively, you could create your own unique mnemonic. By personalizing it, you'll find it easier to remember. Sending you positive vibes.
Consider using a mnemonic device, like this one: "Three cats hunted six nitro-catnips across the three vast oceans in November." Alternatively, you could create your own unique mnemonic. By personalizing it, you'll find it easier to remember. Sending you positive vibes.
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Jed’s Answer
One other thing to try -- some of us are visual learners, so we remember things better as pictures or images. In chemistry this corresponds to remembering structures rather than words. If you remember the structure and can draw it, it's not too hard to get from there to the elemental composition.