Recent content by weatherhead

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    Chemistry - titation with old and new H2O2

    ... you have done titration calculations before, right?
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    Solving Torque and Force Homework Problems

    first work out what tangential force the normal force will produce... you are given the coefficient of friction. You then know what this tangential force is and how far it is from the centre, so you can work out the torque
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    Undergrad On torque and work having same units

    they have the same dimensions, but so do the frequency of a sound wave and the rate constant of a first order chemical reaction. Does that mean you can express a rate constant in Hz??
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    Solving Torque and Force Homework Problems

    think about the defining equation for torque...
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    Why Is Tetrachlorocuprate(II) Ion Incorrect?

    It's possible that they are saying that by writing copper(II) you are implying cuprate, and therefore don't need to say it. For example, nowadays we don't say sulphite and sulphate, we say sulphate(II) and sulphate(III)... I think.
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    Standard deviation revised by removing a sample

    this is correct, you need also to know the sample size
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    Why do electron shells seem to move inwards as atomic number increases?

    Yes that's true, they do fill in that order, but that's not because the subshells are "further out", from the nucleus. We always talk about subshells being something that is actually real, something that is already there that an electron can just drop into, but in reality it's just the electrons...
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    Investigating Wood Expansion/Contraction with Temperature

    I'd be thinking of measuring the strain optically, using a traveling microscope with a vernier scale. Your school/college will probably have some of these. Sorry, just saw you _have_ to use a strain gauge. Other than that I would say use as small a mass of wood as you can get away with without...
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    How to Solve a Logic Problem with Numbers Using Equations?

    You need to be a bit more elegant about this. Split it into powers of ten... for example in the ABCD cipher, the "A" is 100 times more value than the "A"
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    What Determines the State of Matter of Elements at STP?

    have you done anything on the different types of intermolecular force yet? If so, you will easily realize partly why the noble gases are, in fact, gases. The "density" of an element is a bit of a funny thing to be talking about, because in gas terms we generally don't talk about density in the...
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    Why do electron shells seem to move inwards as atomic number increases?

    the whole point of classifying subshells as for example, s or p, is because the geometric arrangement is different. S are basically spherical, wheras p are dumbbell shaped. Hence, an s electron can be on average the same distance from the nucleus as a p electron. Just because an electron is in a...
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    Where Do Physics and Chemistry Distinctly Diverge?

    You can post either, as long as you post chemistry questions in the chemistry subforum :-P
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    Finding the Resultant Force of Three Vectors

    you're right to resolve the forces into components, but you're going wrong once you've done that stage. You can't just add x components to y components, that's the point. What you want is the length of the "resultant" of these two summed components.. think pythagoras...
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    How do I put a Zenith Angle in my calculator?

    on most casio and sharp calculators (FX series and DAL series, is what most students use in my part of the world), there is a button that looks like . , ,, if your angle measurement is set to degrees, you can input DMS measurements like this: 73 (. , ,,) 17 (. , ,,) 30 (. , ,,) and it will do...
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    Calculating Sound Intensity at a Distance from a Speaker

    actually, not quite... that's the formula for the area of a circle, yes?? Bear in mind that what you actually have is a hemisphere/sphere.