Chem 163: Exam 2

What is the maximum number of electrons can each electron shell hold?

2n^2

What is the electron capacity of subshell s?

2

What is the electron capacity of subshell p?

6

What is the electron capacity of subshell d?

10

What is the electron capacity of subshell f?

14

Rank the subshells from lowest to highest energy:

s-p-d-f

How do you identify valence electrons?

look at last shell (principle quantum number)

Atomic size Trend:

increases going down group

decreases going across period

first ionization energy trend:

decreases going down group

increases going across period

Ionic Compounds:

formed by attraction of ions with opposite charges, atoms accept or donate electrons.

(metals and non-metals)(ΔEN usually greater than 1.9)

Electrostatic Force:

the attraction or repulsion of particles because of charge

What does coulomb's Law tell us?

the smaller the distance between the charges, the stronger the force holding oppositely charged ions together

Covalent Bond:

bonding that shares electrons between two or more atoms

(non-metal to non-metal)

electronegativity trend:

decreases going down group

increases going across period

What does it mean if the bond of atoms have a large difference in electronegativity?

it has polarity (greater deltaEN, greater polarity)

How do we name ionic compounds?

Metal is written is as the element name, non-metal has the suffix

-ide to the name (Lithium Chloride)

How do we name covalent compounds with two non-metals?

the less electronegative element is treated like a metal and keeps the elemental name, and the other element has the suffix -ide (Hydrogen Chloride)

How do we name polyatomic ions?

the metal is named first using the elemental name, the polyatomic ion is named second

Steric Number:

the sum of the number of atoms attached to the central atom plus the number of lone pairs on the central atom

Steric Number: 2 (2+0)

Bond Angle: 180

Molecular Shape: Linear

Steric Number: 3 (3+0)

Bond Angle: 120

Molecular Shape: Trigonal Planar

Steric Number:4 (4+0)

Bond Angle: 109.5

Molecular Shape: Tetrahedral

Steric Number: 4 (3+1)

Bond Angle: 107

Electron-Group Shape: Tetrahedral

Molecular Shape: Pyramidal

Steric Number: 4 (2+2)

Bond Angle: 105

Electron-Group Shape: Tetrahedral

Molecular Shape: Bent

Steric Number: 3 (2+1)

Bond Angle: 118

Electron-Group Shape: Trigonal Planar

Molecular Shape: Bent

Intermolecular Forces:

the forces that hold neighboring molecules together and is determined by molecular shape

Intramolecular Forces:

the forces inside the molecules

Dipole Moment:

the amount of change separated x distance over which it is separated

Polar Vectors:

has a vector greater than 0

Non-polar Vector:

has a vector equal to 0

ΔEN greater than AROUND 1.9 is an ____

ionic bond

Polar Covalent Bonding

Two atoms share electrons unequally because one atom pulls the electrons closer to itself. Somewhere between Polar and Covalent Bonding(two non-metals)

The difference in electronegativity is typically between 0.4 and 1.7