Exam 2 Flashcards
What is an alkene?
Contain one or more Carbon-Carbon double bonds
What is an alkyne?
Contain one or more Carbon-Carbon triple bonds
What is an alkene classified as?
Unsaturated hydocarbons
What is an alkyne classified as?
Unsaturated hydrocarbons
What does sigma form a bond between?
Overlapping sp-sp orbitals
What does a side to side overlap between 2p orbitals form?
A pi bond
Why do you start a curved arrow on a pi bond?
It has the most energy to react because its electrons are stored in unhybridized orbitals
What is the relationship between bond length and sp orbitals?
When S character increases, bond length gets shorter because the spherical shape is shorter than that of the elongated P orbital
What is an isomeric alkene?
Differ in the position of the double bonds.
What is a constitutional isomer?
Molecules with the same molecular formula, but different in atom connectivity.
What are stereoisomers?
Compounds with identical connectivity that differ in the spatial arrangement of their atoms.
What is a sterocenter?
An atom is a stereocenter when the exchange of 2 bonded groups gives stereoisomers.
What is this substituent group?
Vinyl
What is this substituent group?
Allyl
What is this substituent group?
Isopropenyl
How do you assign the highest priority?
Higher priority goes to the substituent group with the highest atomic number. If the atoms are the same, continue moving outward until the first point of difference.
What does E mean?
Trans/Opposite sides of the molecule
What does Z mean?
Cis/Same side of the molecule
What is an unsaturation number?
Gives info on number of rings and/or pi bonds.
Why are aklenes & alkynes unsaturated?
They don’t have the max # of hydrones since there is a C-C double or triple bond.
What is the degree of unsaturation?
Each ring and/or pi bond reduces number of hydrogens by 2.
What is the equation to determine unsaturation number?
Why is an alkene more polar than an alkane?
The C-C double bond creates partial negativity.