Recent content by Samurai33

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    G-field - help very confused

    Homework Statement please look at the following statements: 1: due to air resistance, total energy of a satelliit will decrease gradually, dissipated into internal energy. As T.E. = -GMm/2r, r will decrease, hence K.E. increases (K.E.=GMm/2r), implies speed increses. (T.E.=PE+KE) 2: 98...
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    Florine with water and aqueous Fe2+

    Florine can oxidize water to oxygen and hydrogen floride. When reacts with aqueous Fe2+, water is being oxidized to give hydrogen peroxide and some OF2,(due to the strong oxidizing power of F2?) so the reaction is unsuitable to carried out, right? That means meanwhile Fe2+ is also oxidized to...
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    Buffer action

    To be more specific, it cannot be used for calculating pH of buffer with strong acid and its salt??
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    Intensity on IR-spectrum

    can anyone explain??
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    Buffer action

    could the equation - pH=pKa+log([A]/[HA]) - be applied for the case of strong acid? Although the percentage of dissociation of strong acid/base is very high, there still exists a equilibrium, right? secondly, if i tried to explain the resistance in pH of buffer *in terms of* the above...
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    2 Questions:metling point in unsaturated fat; nerve impulses

    sp2 is plannar(120degree) and sp3 is tetrahedral(109.5degree), so what? Is there any picture showing the "repulsion"? It would be easier to vitrualize it, thx!
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    Intensity on IR-spectrum

    http://x5.freeshare.us/view/?121fs535045.jpg In the above diagram, what does the % of transmittance means? I know the % of transmittance is the reverse of % absorption, but there are more C-H bond per molecule than C=O, why the intensity for C=O is higher(higher absorption)? I really have no...
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    2 Questions:metling point in unsaturated fat; nerve impulses

    sorry, for the first point about the hybridization, could you further elaborate it? I simply have no idea.........thanks
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    2 Questions:metling point in unsaturated fat; nerve impulses

    Sorry for the delayed reply, i've just done a little search, found out that C=C in unsaturated fatty acids causes a bend in the hydrocarbon tail, making the "V" shape as described by ypu, so i guess it's probably related to the dense e- cloud in the C=C, so by electron cloud repulsion, a bend is...
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    2 Questions:metling point in unsaturated fat; nerve impulses

    First, i dont think that the packing efficiency can be a good indicator of the strength of intermolecular forces, as for the case between cis-but-2-ene and trans-but-2-ene, the cis one though having a perment dipole, its melting point is lower due to the higher packing effieiency(more...
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    2 Questions:metling point in unsaturated fat; nerve impulses

    sorry for that.....didnt notice that@@ For the second questions, i've made some hypothesis and about the first questions, i would suggest that since the triglyceride is having 3 hydrocarbon tail, if any of the tail is having C=C and with the rest two being saturated, then the pasking efficient...
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    2 Questions:metling point in unsaturated fat; nerve impulses

    Here is my first question: As we all know that, fat and oil(lipid) are triglycerides, they differ in the hydrocarbon tail with fat(saturated fat) without C=C, whereas lipid(unsaturated fat) having C=C in the hydrocarbon tail. My question is why does having a C=C will lower the metling point...
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