Description: Please complete ALL the problems in Ch 4 of "Second Language", and the ODD problems in Chapters 5 and 6 of "Second Language", as well as the following problem set.
Total Problems: 12
Let's perform conformational analysis on 2-methylbutane along the C2-C3 bond. We'll use the energy chart given below.
First, draw out the Newman projections along the C2-C3 bond, rotating the front carbon (C-2) by 60 degrees clockwise each time while keeping the back carbon (C-3) stationary.
According to the table above, how much energy does each conformation "cost?"
Second, make a plot of the total energy value for each Newman projection versus its dihedral angle.
Rank the following compounds in order of decreasing boiling point.
Also, make a guess about their relative solubilities in water. Explain your reasoning.
Draw all possible resonance forms for each structure below. Use curved arrows.
Note that some structures only show charge, and not implied protons or lone pairs!
Convert each formula to a carbon skeleton diagram, or vice-versa.
For each molecule, determine the formal charge of the indicated atom.
For each molecule below, draw in all implied lone pairs and/or protons (hydrogens) based on the formal charge shown.
Draw all possible resonance forms for each structure below. Use curved arrows.
Note that some structures only show charge, and not implied protons or lone pairs!
Draw all possible resonance forms for each structure below. Use curved arrows.
Note that some structures only show charge, and not implied protons or lone pairs!
Draw all possible resonance forms for each structure below. Use curved arrows.
Note that some structures only show charge, and not implied protons or lone pairs!
Rank each set of compounds in order of decreasing boiling point (1 = highest boiling point):
a) ethane, n-octane, n-pentane
b) n-butane, 1-butanol, 1-chlorobutane.
c) n-octane, 2-methylheptane, 2,5-dimethylhexane
(Note that the n- prefix before an alkane just means that it's one chain, without any branching.)
α-D-Glucose is shown below. Draw its two chair forms. Which conformation is more stable? Explain.
I recommend using the common convention wedge = "up" and dash = "down."
Two stereoisomers of trimethylcyclohexane are shown below (compounds A and B). Compare cyclohexane chair forms to determine which isomer has a lower heat of combustion. Explain your reasoning.