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When 1 mol of potassium chlorate crystals, KClO3, decompose to potassium chloride crystals and oxygen gas at constant temperature and pressure, 39.0 kJ of heat is given off.  Write a thermochemical equation for this reaction. [Make sure to use subscripts and superscripts where applicable.  If you need any Greek symbols or arrows,  they are located in the math equation (square root symbol) in the tool bar immediately above this question.]

Match: Note there are more matching possibilities than needed.

  Equations:              q = (m)(c)(ΔT)              1 cal = 4.184 J                   ΔH°rx = ∑n  ΔHf°products − ∑n ΔHf°reactants E = hc/

Calculate the energy of the green light emitted, per photon, by a mercury lamp with a frequency of 5.49 × 1014 s-1.  

Which of the following combinations of quantum numbers is permissible?

Using the following equation for the combustion of octane, calculate the amount of heat involved when  0.7520 moles  of  octane react.   2 C8H18 + 25 O2  → 16 CO2 + 18 H2O                         ΔH°rxn = -11018 kJ (If you wish, you can show math work for possible partial credit.)

Fill-in the blanks: a) The electron in the n=3, l = 1 is found in the the [a] subshell.         b) An i subshell has [b] orbitals.       c) Consider P and P3-.  Which one has the largest radius, the atom or the ion?  (Note: Do not write the symbol, in the space write the word atom or the word ion.) The [c].  d) Of the elements Ba, Pb, Cs and Tl, the one with the highest first ionization energy is [d].  e) Of the subshells, 3s, 2p, 3p, 2s, [e] has the highest energy.     f) For the subshell 7p, the value of the principle quantum number is [fa] and the value for the angular momentum quantum number is[fb]. g) The following condensed orbital diagram belongs to an ion, X3+.          The chemical symbol of X is [g].  

Which of the following statements is the most accurate description of the sliding filament mechanism?

Name three pieces of information which you know about acetylcholinesterase.

The most lethal biological toxin in the world is