Refresher Flashcards
Theme of electronegativity
Top right corner is most electronegative
What element can you just ignore when drawing structures
O
What structures are monovalent and what does that mean
H and halogens (F, Cl, Br, I) and they can just make one bond
How to determine degrees of unsaturation
[(2n+2)-actual]/2
What is DBE
degrees of unsaturation, every one means a double bond
What is an isomer
a different form of the same structure
How do you count formal charge
count each bond as one and each electron as one and any extra from expected (from periodic table) is - and less is +
What is the smallest ring
3 points
How do you know what the best structure is when they both have a charge
charge is on the most electronegative atom
On a bond line, what is the rule about writing carbons
Once you write a carbon, you much write the hydrogens attached to them
How many carbons are needed for bond-line
at least 3
How many sigma bonds are in a pi bond
2
4 VSPER Units hybridization, geometry, bond angle
sp3, tetrahedral, 109.5
3 VSPER Units hybridization, geometry, bond angle
sp2, trigonal planar, 120
2 VSPER Units hybridization, geometry, bond angle
sp, linear, 180
How do more bonds affect the length
more bonds = stronger = shorter
Rules for determining to major resonance contributor
filled octet, minimum charge, positive charge on less electronegative atom and negative on most electronegative atom
pi bond and lone pairs should be in what relation to each other
next to each other
When averaging bond length, the number favors what
favors the majority resonance structure
London Forces
interactions between electron clouds
How does surface area affect melting and boiling point
higher surface area, higher mp and bp
Dipole-dipole
positive end of one dipole interacts with the negative end of another dipole
Hydrogen bonding
very strong dipole-dipole interaction when H bonds with N, O, or F
How does H bonding affect bp
makes it go up
How does symmetry affect mp
makes it go up
What does hydrogen bonding have to do with solubility
compound will be soluble if it has both hydrogen donors and acceptors and 5 carbons or less; if they have only acceptors they will be soluble if they have 3 carbons or less
