Organic Molecules Flashcards
(21 cards)
Shape of alkane
Tetrahedral shape: 109.5
4 bonding pairs
0 lone pairs
Electron pairs repel
What are the intermolecular forces between alkane molecules?
London Forces
What factors affect the size of alkane London Forces?
Chain length and Branching
Alkane + halogen ——> ?
Conditions?
Alkane + halogen ——> Haloalkane + Hydrogen halide
Requires UV radiation
What type of mechanism is: alkane + halogen?
Radical Subsitution
In radical substitution what leads to unwanted products?
Non-specific substation and further substitution
Why do alkanes have low reactivity?
High bond enthalpy and low polarity of the C-C and the C-H bonds
What is a pi bond?
the sideways overlap of adjacent p-orbitals above and below the plan of the carbons.
Bond angle and shape in alkenes?
3 regions of electron density
Electron pairs repel
120 degrees
Trigonal planar
Definition of structural isomer
Molecules with the same molecular formula but different structural formula.
Definition of stereoisomers
Molecules with same molecular and structural formula but different arrangement of atoms in space.
Requirements for E/Z isomerism
Two different groups to be attached to each carbon atom of the Carbon to Carbon double bond
The Cahn, Ingold, Prelog rule
Assign priority based of the Atomic Number of atoms closest to C
What is cis-trans isomerism?
When on each end of the carbon to Carbon double bond there are the same groups each CHF=CHCH3
Alkene + halogen/hydrogenhalide ——> ?
Alkene + halogen ——> (di)haloalkane
Alkene + hydrogen halide ——> (mono)haloalkane
Alcohol shape
Tetrahedral (alkane)
4 bonding pairs
0 lone pairs
Electron pairs repel
Non-linear (C-O-H)
2 bonding pairs
2 lone pairs
Electron pairs repel
Lone pairs repel more than bonding pairs.
Why do alcohols dissolve well in water
They can hydrogen bond
Reflux of secondary alcohol
+ [O]
H2SO4 and K2Cr2O7
Ketone
Elimination of secondary alcohol
Requires Conc H2SO4 or Conc H3PO4
Creates alkene + water
Substitution of Alcohols
Requires NaX and H2SO4
Creates Haloalkane + water
Haloalkane + NaOH ——> ?
Haloalkane + NaOH ——> Alcohol + NaX
