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Which of the following unit cells has a packing efficiency of 1 (atoms)?  

For the solution described below, choose the best energy diagram that represents the solution. When sodium chloride dissolves in water the enthalpy of solution (ΔHsoln) is equal to +4 kJ.  The lattice energy (ΔHlat) for NaCl is -778 kJ and the enthalpy of solvent (ΔHsolv)for water is 285.82 kJ/mol.  

(**Show work on separate sheet of paper along with final answer.  Also type final answer in the provided box below the question here as well.) Calculate the amount of energy (in kJ) required for a 132-g sample of benzene (C6H6, M = 78.115 g/mol) at 55.2 °C to drop to 3.0 °C? *The normal freezing point for benzene is 5.85 °C and boiling point is 79.85 °C. Physical data associated with benzene is provided below, but all of the data may not need to be used. (7 pts.) Cs, solid = 1.51 J/g·°C                     Cs, liquid = 1.73 J/g·°C              Cs, gas = 1.06 J/g·°C ΔHfus = 9.80 kJ/mol                      ΔHvap = 33.9 kJ/mol

Which of the following statements (if any) is true.

(**Show work on separate sheet of paper along with final answer.  Also type final answer in the provided box below the question here as well.) A solution containing 0.71 g of Ca(OH)2 (M= 74.093 g/mol) in 625 mL of water at 298.15 K, calculate the osmotic pressure of the solution in mm Hg. Assume the solute completely dissolves.(1 atm = 760 mm Hg) (7pts.)

Select all the correct pitches for the key of Bb harmonic minor.

A succession of eight pitches, ascending or descending, is performed in the MP3 file below. Select “True” if the pitches form a major scale, “False” if they do not. A2-1j.mp3

The dominant triad in natural minor is minor in quality.

The third of an Db major triad is:

A succession of eight pitches, ascending or descending, is performed in the MP3 file below. Select “True” if the pitches form a major scale, “False” if they do not. A2-1b.mp3