Recent content by Simon_Moore

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    Can I mix these 3 chemicals together?

    If you mix together toluene, cyclohexane and benzene they will basically just mix. Thats it. Nothing else will happen.
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    Can I mix these 3 chemicals together?

    Well, some materials' MSDS's will only be available from the company that manufactures them, whereas common commodity materials MSDS are freely available. Thats the point I was making.
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    Sort these substances by boiling point

    Boiling point is a measure of the amount of thermal energy that has to be provided in order to overcome whatever intermolecular forces exist between the molecules of the material when it is in liquid form. Therefore, look at each of the species in question and work out which ones would likely...
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    Average diameters of colloids

    Can't you just work it out by taking the surface area of a sphere and working back to get the radius? You know the total surface area of the total particles in 1 litre, and you know how many particles there are in 1 litre, so from that you can work out the surface area of 1 particle.
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    Can I mix these 3 chemicals together?

    They are all miscible in all proportions and will simply form a blend, no reaction will occur. Benzene is indeed carcinogenic, toluene is also toxic by inhalation. MSDS's for all three are available in public doman, just Google "MSDS Benzene" etc.
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    Distinguish between polyunsaturated vegetable oil and petroleum oil

    I assume by "petroleum oil" they are referring to either a paraffinic or naphthenic mineral oil. These do not contain triglycerides or esters, they are a mixture of paraffinic and naphthenic hydrocarbons, with somewhere between 0 and 15% aromatic hydrocarbons. There may also be some very minor...
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    Polar bonds

    In the simplest model, the degree of polarity of a covalent bond is determined by the relative difference in electronegativity of the two atoms. Therefore, something like the carbon-carbon bond in ethane CH3-CH3 would be virtually zero polarity, as the two atoms are the same (both carbon), and...
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    Liquids as insulators

    The oil in the You Tube video is a "white oil" - the canister is labelled "light mineral oil - light laxative". That specific one would be medical quality, but assuming you're not going to actually drink any of it, a technical quality one would be fine. Marcol 82 by Exxon Mobil (thats the...
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    Need Help With My Unit Assignment (DUE December 5th)

    You should be able to have a stab at the first one.... You have the balanced equations and you're told that you have to produce what I assume is 1.0 x 10^6 (100,000) kg of nitric acid. If you know how many moles that is, then from the stoichiometry shown in the equations you can work out...
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    Liquids as insulators

    Oils used as electrical insulators (dielectrics) is an area of expertise for me, as I worked in developing them for about 15 years. Most oils need some additional treatment to remove polar impurities and increase the resistivity, however, something like a white oil (liquid paraffin) would be...
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    Can unsaturated fats become saturated?

    Must be "reduced" calories....(sorry)
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    Chemistry kenitics problem

    The rate constant is just 7 times the original rate constant, so can't you relate the two together as K1 and 7.K1, and then if you solve for T2 you should be able to get the K1s and the As to cancel out.
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    Medical Plastic Water Bottle Use

    If its unsafe to do this because plasticisers leach out of the bottle, then surely that would happen whether the bottle was being reused, or simply sitting in the store filled with mineral water waiting to be sold! I can't see why rinsing them out and reusing them would create the problem...
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    Change in enthalpy help?

    I would do it by working out the total amount of temperature rise over the whole reaction mixture (which you have been given), and then assume that the density of the two solutions is still 1.00 g/cc (which they will be, as near as makes no odds). The delta H will then be: Delta H = m.c.t...
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    Are hydrocarbons miscible?

    Petroleum jelly is not transparent for the same reason that paraffin wax is not transparent. The wax contains a range of molecular sizes, so the crystal sizes show a fair degree of polydispersity which means that light tends to be scattered by them. When molten petroleum jelly cools the...
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