Recent content by broegger

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    Solving Basic Probability Exercises with Intuition

    :-) Precisely. Hopes somebody weighs in...
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    Solving Basic Probability Exercises with Intuition

    Hmm. In (a) there are two ways of getting all assignments wrong (if the correct one is 123, then these are 312 and 231) and there are 3*2*1 = 6 possible assignments. If his guesses are random this yields Pr(all wrong) = 2/6 = 1/3. In (b) I count 9 ways of getting all assignments wrong out of...
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    Solving Basic Probability Exercises with Intuition

    Yeah, I think I'll do that, although it gets rather complex in (b). A slight problem though: when I count the combinations I get 3/8 in (b), but when I calculate it using the multiplication rule I get 1/4 :eek:
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    Solving Basic Probability Exercises with Intuition

    Hi. I'm a math instructor and this problem is given to 1. year economics students. 1. The problem statement In an episode of the TV show "All in the Family", Mike claimed that he could identify different brands of cola by taste alone. He was challenged and presented with three glasses, one...
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    Conditional Distribution of Multinomial Random Variables

    I've been staring at this for hours. Any hints? Let the vector Y = (Y_1,Y_2,\dots,Y_k) have a multinomial distribution with parameters n and \pi = (\pi_1,\pi_2,\dots,\pi_k): \sum_{i=1}^{k}Y_i = n, \quad \sum_{i=1}^{k}\pi_i = 1 Show that the conditional distribution of Y_1 given...
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    Optical Isomerism of [Fe(H2O)6] Complex

    It's in the context of simple http://wwwchem.uwimona.edu.jm:1104/courses/CFT.html". I don't think there's any unobivious rules here, but I don't know...
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    Optical Isomerism of [Fe(H2O)6] Complex

    I see your point. If we assume that every H2O molecule occupies one ligand space and does not interact with it's neighbors -- would I then be correct? It's an introductory course, so I assume there's no pitfalls.
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    Optical Isomerism of [Fe(H2O)6] Complex

    Hi. I'm asked the following question: What isomers does the complex [\text{Fe}(\text{H}_2\text{O})_6] give rise to? Is it optically active? My answer to the first question would be 'none': The 6 identical H2O molecules are arranged in an octahedral fashion around the central Fe-atom, so...
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    Solving Intermolecular Bonding Exercises: B2H6, CH4, NH3 & H2S

    c) Still in the dark. Can't relate these things to the activation energy... sorry. f) Oxygen is more electronegative than nitrogen, so the OH-molecule has a greater dipole strength than the NH-molecule and therefore the hydrogen bond is stronger in the former case (O-H---O). Right? Thanks...
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    Solving Intermolecular Bonding Exercises: B2H6, CH4, NH3 & H2S

    Hi. I need help with (part of) this exercise: c) By considering the differences in bonding determine which of the combustion reactions (in part a) I have written combustion reactions for the following hydrides: B2H6, CH4, NH3 and H2S) must be expected to have the lowest energy of activation...
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    Solving Solubility Problem: I_2\text{(s)} in KI(aq)

    Hmm, not sure. But I think I know how to do it now. Thanks.
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    Solving Solubility Problem: I_2\text{(s)} in KI(aq)

    It will shift to the right, so the solubility will go up (consistent with my result.) I should compute the I3- concentration and add it to the I2(aq) concentration to find the new solubility, right?
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    Solving Solubility Problem: I_2\text{(s)} in KI(aq)

    Hi. I'm preparing for a chemistry exam and I have trouble with this former exam problem: The solubility of I_2\text{(s)} in water at 25ºC is 0.0013 M. Calculate the solubility of I_2\text{(s)} in a 0.1 M solution of KI(aq) by considering this equilibrium: I_2\text{(aq)}+I^-\text{(aq)}...
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    Why Does Cs React More Violently with Water than Li?

    I have no idea, just quoting from the book, basically. Doesn't Li- and Cs-solids exist? I'm a lousy chemist, I know. I would think that "quietly" means slow and "violently" means fast, so the statement is that the reaction rate of Cs + water is larger than the reaction rate of Li + water. I...
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    Why Does Cs React More Violently with Water than Li?

    The Li atoms are smaller, but how does that affect the reaction?
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