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Flashcards in Chemistry Deck (17):
1

elements with incomplete octet in their v.

hydrogen and helium (2)
beryllium (4)
boron (6)

2

elements with expanded octet in their v.

elements in period 3. Specifically,
Phosphorus (10)
Sulfurous (12)
Chlorine (14)

3

A molecule with odd number electrons in v.

NO- nitric oxide with 11e

4

elements that will always follow octet rule

Na, Mg, C, N, O, F

5

The periodic trend that determines whether a covalent bond is polar

electronegativity

6

this compound form crystalline lattice in solid state

ionic compounds

7

physical properties of ionic compound

high MP and high BP
soluble in water and polar solv.
In aq. or molten form are great conductor of electricity.

It's all because of the electrostatic forces. The elements are fully charged. The strongest intera-molecular force.

8

Naturally occurring diatomic elements

form number 7 on the periodic table (exc. H) and most ate in VII A:
H2, N2, O2, F2, I2, Br2 and Cl2

9

diff. in EN of polar cov. bonds

0.5- 1.7
Anything greater than 1.7 will become ionic since one element will monopolize the entire e cloud.

10

How to determine which subshell fills first

Rule: lowest (n+l) fills first
When two equal numbers, then the one with the lowest n fills first.
Paulis exclusion rule: the orbital with lowest E fills first ( as distance from nucleus increases, E increases.)

11

The formula for the dipole moment of a bond or a molecule

P=qD
D- displacement separating the two charges.

12

coordinated cov. bond

both of the shared electrons originated on the same atom

13

diff. guises of coordinate cov. bonds

lewis acid-base rxn
nucleophile-electrophile rxn
complexation rxn

14

the diff between the ox and formal charge of a molecule

formal charge underestimates EN
oxidation number overestimates EN
e.g. CO2
Formal charge is 0 for C and O's
But oxidation # for O is -2 and +4 for C ( assumes 100% contribution of one element in taking up all the electron cloud).

15

VSEPR SF6
and bond angle

octahedral
90, 180

16

PCl5 VSEPR and bond angle

trigonal bipyrimidal 90, 120, 180

17

The diff. EN of non-polar cov. bonds

<0.5
0.5-1.7 --> Polar covalent