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Offline Gradient

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I have questions specifically about CLEP Chemistry exam
« on: August 13, 2018, 05:07:10 PM »
I sent an email to clep at with these 8 questions. So far, nobody has responded. Would someone be able to answer these questions which are specifically about the CLEP chemistry exam?

  • CLEP's website says I will have access to a periodic table on the exam. What information is given on this periodic table? Does it only give element symbols and atomic masses, or are other properties given, like whether the element is a metal, metalloid, or nonmetal?
  • How accurate are the atomic weights on the CLEP test's periodic table? Are they all given with the same quantity of significant figures? Or do they round off at a specific decimal point?
  • When calculating the answers to questions using the atomic masses given on their periodic table, should I assume that the numerals are exact (having infinitely many significant figures) or uncertain (finitely many significant figures)? For example, if the table gives the numeral 1.008 for the standard atomic weight of hydrogen, then should I consider 1.008 to be infinitely accurate and precise, or should I consider it to be uncertain with only 4 significant figures?
  • If I am given a numeral which has some trailing zeros but does NOT have a decimal point, like the number 400, how should I count the significant figures in that numeral? Does 400 have 3 significant figures or only 1 significant figure?
  • What notation do I need to memorize for thermodynamic quantities, and which notation is used by the exam? For example, is ΔH used to denote change in enthalpy? Is ΔU or ΔE used to denote the change in total energy of a system, or is some other notation used? What about the notation for voltage? Is ΔG used to denote the Gibbs free energy? How is entropy denoted?
  • What sign convention is used for the work done to a system? Let's say that a chemistry problem gives values for change in enthalpy, ΔH = 1 kJ, and work, W = 1 kJ, and I need to calculate the change in total energy, ΔU. However, let's assume that the question does NOT explain whether the quantity of work is being done on the system or by the system. Should I use the formula ΔU = ΔH + W to get 2 kJ or should I use ΔU = ΔH - W to get 0?
  • When discussing quantities of energy, some textbook authors use actual energy units, like eV, J, or kJ, and some use energy-per-amount-of-substance units, like kJ/mol. Which one does the CLEP test use? For example, would the enthalpy of formation of water be approximately equal to -285.8 kJ/mol, even though the "kilojoule per mole" is not a unit of enthalpy? Or would it be a value in J, kJ, or eV?
  • Let's assume that the answer to the previous question is "actual energy units," as in J, kJ, or eV. If that is the case, then what should I assume are the definitions of terms like "enthalpy of formation" and "enthalpy of combustion"? For example. does the enthalpy of formation of water refer to the change in energy when one single molecule of water is formed (so its value would be approximately -2.959 eV)? Or does it refer to the change in energy when one mole of water molecules is formed (so it would be something like -285.8 kJ)?

Please help me by answering these CLEP-specific questions accurately or pointing me toward a professional who can answer these questions.
« Last Edit: August 14, 2018, 02:07:21 AM by sjb »

Offline Borek

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Re: I have questions specifically about CLEP Chemistry exam
« Reply #1 on: August 13, 2018, 07:01:14 PM »
Please don't post emails in the text of your posts. That's a sure way of making bots know them and start to spam them.
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