Recent content by Tom Creswell

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    Calculating Mass and Volumetric Flow of Nitrobenzene: Homework Solutions

    Mix density = total kg / total liters (or total lbs/ total cu ft). Figure out both totals, then divide.
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    Why Do Magnets Attract Certain Metals?

    I don't know either, but here are some things to google. Paramagnetism, orthomagnetism. Iron, Cobalt and nickel exhibit this behavior, something to do with un-paired electrons in p or d shells. Try a freshmen college chemistry book.
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    Some quick and simple help please - Tetrahedral Compounds

    Carbon has 4 valence (bonding) electrons, and four atomic orbitals- s, px, py, pz. The S is spherical, the p's are dumbbells, oriented in each of three orthoganal directions. These can be re-shuffled (linear combinations of atomic orbitals) to four sp3 orbitals. These are spatially oriented to...
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    Process engineering mass balance in the douglas aproach

    Mole proportions of each species are EB= 0.98 - x-y-z Styrene= x H2= x-z Bz = y+0.02, ethylene= y Tol and methane= z ----------------- Specify x= 0.3, 0.4, 0.5, 0.6 Then Figure out y, z as a function of x (two formulas) Prorate all the moles above to get the right amount of product. Do...
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    Energy is needed to drive an ecosystem

    This question requires a context. Or else if general, it requires a general knowledge of science. My thougt is solar energy is fundamental- it heats plants and animals, enables photosynthesis. When animals eat the plants, their enzymes break apart the chemical bonds obtaining heat or energy...
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    Effect of Ethanol and Water Mixing on Randomness: A Discussion

    I know the answer (mixture is always more random, meaning higher entropy, than two pure substances) but not how to explain it. Maybe the explanation is that you can't separate a mixture without spending energy. Another thought- visualize baseballs (H2O molecules) and footballs (C2H5OH), in two...
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    Why Doesn't an Egg Harden When Boiled at High Altitude?

    You guys are close. Cooking is a heat transfer problem. To make heat go from the hot object (boiling water) to the cold object (egg) you need a temperature difference (Th-Tc). Since water's boiling point temp is reduced at altitude, the rate of heat transfer (proportional to Th-Tc) is less...
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    HELP Pressure Change for equation without volume

    I agree with Ygg.. Assume volume and temperature are the same at beginning and end. Then the pressure is proportional to moles. The equation is N2+3H2 -> 2NH3. Assume this has an extent of x (x moles of N2 reacted). Starting moles N2=5, H2=10. Ending moles N2=5-x, H2=10-3x, NH3=2x. Total...
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    Chemistry Molecular Formuals from Empirical Formula

    ==================== You got a ratio of 2.57:1. instead of rounding to 3, try 5:2, which is a lot closer. Then your formula is P2O5 or P4O10. This makes sense since P and O have oxidation numbers of +5 and -2, so the electrons balance out to zero.
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