Recent content by silversurf

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    Sound Wave Attenuation: Why Does Water Attenuate More?

    Why does water attenuate sound waves more than air? Is it because of it's bulk modulus? This is what I understand. Speed through a medium is determined by the elastic component over the inertial component. Since water has a much greater bulk modulus (elastic component) than air, it makes the...
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    Effect of Solvent Polarity on Rf Value in TLC

    How does polarity of the solvent affect the Rf value? I was going over a problem in my book that said that polarity would increase the Rf value of both the polar and nonpolar analyte due to increased solubility. This doesn't make sense to me because wouldn't the solubility of the nonpolar...
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    Why is E2 preferred over SN2 for 2-chlorobutane with sodium ethoxide?

    Actually never mind, I just realized the reason why is because it's a weak base.
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    Why is E2 preferred over SN2 for 2-chlorobutane with sodium ethoxide?

    Hi Chemisttree, I think I understand but I'm not sure. I'm confused on why you used pka of acetate, for comparison, to determine basicity. Are you just using this as a starting point converting to pkb and then looking at basicity? If so couldn't we just look at each pkb and pick the one with...
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    Why is E2 preferred over SN2 for 2-chlorobutane with sodium ethoxide?

    Homework Statement Why would this reaction favor E2 over SN2? Since its a secondary halide reacting with a strong base/nucleophile, and all other conditions being equal isn't SN2 favored? Or is ethoxide somehow a stronger base than nucleophile? If so, how can you tell that it's a better base...
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    Heat of solution and vapor pressure

    I am having trouble with the relationship between these two. My book says that negative heat of solution forms stronger bonds and lowers vapor pressure and positive heat of solution forms weaker bonds and raises vapor pressure. Shouldn't vapor pressure be higher for negative heat of solution...
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    Why Are the Top Methyl Groups Not Chemically Equivalent?

    Homework Statement I attached a picture of the molecule. My question is why are the methyl group at the top not chemically equivalent. The answer says that this molecule makes three singlets in HNMR but I was thinking it should make only 2 because the top methyl groups are chemically...
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    What is the correct concentration of Cl- in various aqueous solutions?

    Oh yes I understand now. I got confused because I thought we had to factor in temperature somehow. But yes I see how you get a two molar concentration and a 1 molar concentration when you solve for moles and liters and solve for molarity. Thanks.
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    What is the correct concentration of Cl- in various aqueous solutions?

    Homework Statement Which of the following aqueous solutions has a Cl– concentration of 2 m at 25°C? A. 271 g of HgCl2 in 55 mol of H2O B. 271 g of HgCl2 in 22.5 mol of H2O C. 53 g of NH4Cl in 55 mol of H2O D. 53 g of NH4Cl in 22.5 mol of H2O. Correct Answer...
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    Why choose /100 over x100?Why Divide by 100 when solving decibels?

    I'm having difficulty understanding the solution to this question. "A source creates a sound that is observed at 200 Watts per meter squared. If the intensity level of the observed sound decreases by 20 decibels what is the decrease in observed intensity? The way I solved it was I saw 20...
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    Vapor pressure and atmospheric pressure

    Got it, thanks so much!
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    Molality for compound with 2 particles

    Oh it makes perfect sense, I wasn't thinking about the equation. Thank you both so much!
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