It's not every day that one learns something relevant to life in one's Organic Chemistry class. Well, this happened in one of my most recent lectures, so I wanted to share that with y'all. It concerns dirt, and who on this planet hasn't had to deal with dirt in everyday life?
We already know that dirt is made up of organic molecules, since it is composed of living and dead things. However, it is mostly non-polar, meaning that carbons and hydrogens make up most of it. Oxygens and other electronegative atoms would create polarity in the molecules, so obviously these are either not present or present in very small amounts. Why is this important? Because, as they say, "like dissolves like." If you get dirt on your clothes or skin, you probably want to get it off. But water alone will not accomplish this. Why? Because water is a polar solvent, and will only wash away other polar compounds, and we have established that dirt is non-polar. Luckily for us, there is a solution (no pun intended) for this problem.
As it turns out, soaps contain both non-polar and polar ends. They contain long hydrocarbon tails with polar head groups containing electronegative oxygens. When soap comes into contact with dirt, it orients itself to place the non-polar tails with the dirt and the polar groups away from the dirt. The non-polar interactions cause the soap and the dirt to be almost linked. Then water comes along, "sees" the polar groups on the soap, and is able to wash away the soap, along with the dirt. So, we can say that soap makes dirt somewhat polar in order to get water to dissolve it. Pretty neat, huh?
So, the next time you're washing your clothes or taking a shower, you'll know why you need soap. Not only because it makes everything smell good, but because without it, everything would be a dirty mess.
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Hmmm, can't say that it enhanced my learning experience. But thanks for giving us "all the dirt" on soap.
You are just the most interesting kid on the planet.
Now when you say I'm interesting, how do you mean that? Is it, "Wow, he's so interesting! I feel priveliged to be related to him!" Or is it, "Oh, that Sean sure is interesting. I don't know how I'm related to him!" ???
I am so proud to be related to you, your mom, your grandparents, your whole family.
I have to agree with the accolades. I took chemistry in college, but not organic chemistry. Very cool info.
I did not know that "like disolves like" and find it fascinating. Washing the dirt off clothes now makes sense. Is soaping up necessary when you are not dirty? If you have merely sweated, and sweat is water based, do you need soap to shower? I am aware that human perspiration has no oder until it is combined with bacteria. Does a soapless shower wash away bacteria?
That is a good question. We know that soap will help you smell better after you sweat, but is it necessary? I seem to recall that Ryan and I helped Aunt Dawn in her yard/flower beds one summer, and after working for a while we went swimming. I don't remember being dirty (or smelling) afterwards, so maybe that answers your question.
If you went into a swimming pool there is chlorine in it and that will kill the bacteria. Much less chlorine in shower water, still need soap? Or, is the soap only used for it's perfuming?
You are right about the chlorine, Grandpa. I thought about that right after I wrote that comment. I would assume that if you aren't actually dirty, you don't really need soap except for the scent. Even if you use unscented soaps (as opposed to floral or other smells), the soapy smell is better than the sweaty smell. If I ever take a soap-less shower, I will be sure to let you know how I fare.
Interesting info. How does DRY cleaning work?
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