please compare and contrast the hybridization of ethylene and butadiene: butadiene ethylene SP orbitals: SP orbitals: P orbitals: P orbitals: Pi bonds: Pi bonds: in relation to Huckel theory: in relation to Huckel theory:

Draw a 3D representation of the molecule penta-1,2,3,4-tetraene using the following EXPLICIT instructions: sigma bonds in the plane of the paper are normal lines, sigma bonds or orbitals projecting in front of the page are heavy lines, sigma bonds or orbitals projecting behind the page are dashed lines, and pi bonds are shown by drawing the lobes of the p-orbitals and indicating the overlaps. What is the hybridization of each atom (except H) in this molecule?

Explain using valence bond theory, molecular orbital theory and/or aromaticity.

Pyrazine, C4H4N2, is used in the synthesis of vitamins and drugs. The molecule can be thought of replacing two -CH units in benzene with a nitrogen atom in each of the 1,4- positions. pyrazine Describe the o and a bonding in pyrazine by analyzing the hybridization state, valence electron count and o-framework. How many delocalized electrons are present? Explain your answer. How many bonding and anti-bonding 7-type molecular orbitals are present? Explain your answer. Draw the detailed MO diagram of the 7-system. Explain your answer.

Some of the atoms in this diagram of allylcyanide have been randomly labelled with numerals (attached image) Match the following: The hybridization of atom 6       The hybridization of atom 5       The hybridization of atom 1       The hybridization of atom 3       The hybridization of atom 7

. The pyridine molecule (C3H;N) is obtained by replacing one C-H group in benzene with a nitrogen atom. Because nitrogen is more electronegative than the C-H group, orbitals with electron density on nitrogen are lower in energy. How do you expect the MOs and energy levels of pyridine to differ from those of benzene?

Molecule C2H2 SFs- NO3- Lewis structure include lone pairs & formal charges on each atom Resonance structures don't have to include lone pairs; write N/A if there are none Electron Geometry Hybridization on central atom Overlapping orbitals O: O: include value of n in the orbital name (e.g. 1s, not s). Write N/A if that kind T: of bond is not present in T: the molecule Molecular Geometry Bond angle(s) include < as necessary 3D structure and polarity don't have to include lone pairs; draw the dipole arrow on the molecule or write "non- polar"

Describe each highlighted bond in terms of the overlap of atomic orbitals. (If the highlighted bond is not a pi bond, select the blank option from the dropdown menu.) Compound 1: H H H H-C-C–ċ-Ö-H H Molecular orbital type: Atomic orbitals in the sigma bond: Atomic orbitals in the pi bond: Compound 2: H H H H H Molecular orbital type: Atomic orbitals in the sigma bond: Atomic orbitals in the pi bond:

Which one of the following statements is false?     Valence bond theory and molecular orbital theory can be described as two different views of the same thing.     When one considers the molecular orbitals resulting from the overlap of any two specific atomic orbitals, the bonding orbitals are always lower in energy than the antibonding orbitals.     Molecular orbitals are generally described as being more delocalized than hybridized atomic orbitals.     One of the shortcomings of molecular orbital theory is its inability to account for a triple bond in the nitrogen molecule, N2.     One of the shortcomings of valence bond theory is its inability to account for the paramagnetism of the oxygen molecule, O2.

How many anti-bonding pi-type molecular orbitals does 1,3-butadiene contain?