Chem 1127Q > Chapter 3 - Electronic Structure + Periodic Properties of Elements + wavelength/energy > Flashcards
Chapter 3 - Electronic Structure + Periodic Properties of Elements + wavelength/energy Flashcards
So4^-2
Sulfate Ion
NH4+
Ammonium ion
OH-
Hydroxide ion
NO3-
Nitrate ion
CO3^-2
Carbonate ion
PO4^-3
Phosphate ion
Prefix for one?
Mono
Prefix for two?
Di
Prefix for three?
tri
Prefix for four?
tetra
Prefix for five?
penta
Prefix for six?
hexa
HSO4^-1
hydrogen suflate/ bisulfate ion
HCO3^-1
hydrogen carbonate/ bi carbonate
H2PO4^-1
dihydrogen phosphate
What are Ionic Compounds?
Metal + NonMetal
What are Molecular Compounds?
2 or more nonmetals
How do you name a Ionic Compound?
Cation (metal) + Anion (nonmetal) (ends in -ide)
EX: KCl = Potassium Chloride
- DO NOT ADD PREFIXES (thats ONLY for molecular compounds)
How do you name a Molecular Compound?
Anion + prefixes (mono, di, tri, tetra, penta, or hexa)
EX: BrI3 = Bromine triiodide
- If there’s only one of the first anion, DO
NOT put mono
N2O2 = Dinitrogen tetraoxide
How do you name a Ionic Compound with a transition metal cation?
- Find the charge of the anion (the nonmetal).
- The charge of the anion is the amount of electrons needed to reach the noble gases. - The charge of the anion will be the same charge for the cation (transition metal). Write this charge in the formula.
- Remember that if there’s more than one of the cation that the charge might be different from the anion
- EX: Cr3(PO4^-3)2- The charge of Cr is 2 instead of 3 because
3x2 = 6, which is the same for PO4 (-3x2= 6)
- The charge of Cr is 2 instead of 3 because
What happens when you have a negative (-) charge on an atom?
The atom has gained an electron
What happens when you have a positive (+) charge on an atom?
There atom lost an electron
Electron Configuration
1s ->2s ->2p -> 3s -> 3p -> 4s -> 3d -> 4p -> 5s -> 4d -> 5p -> 6s -> 4f -> 5d -> 6p -> 7s -> 5f -> 6d -> 7p
How do you write an electron configuration?
- Follow the ortibal pattern on the periodic table
- If the element has a configuration that includes a noble gas (EX: Kr 18), then you don’t have to write the whole configuration, start with the nearest noble gas then write out the rest
EX:
S = [10Ne] 3s2 3p4
How do you write an electron configuration for a cation or anion?
If you have a cation, electrons are lost from the “s” orbital FIRST, then d orbital
If you have an anion, electrons are added to the d, p, or f orbitals depending on where the original element with no charge ends.
What is the trend of the relative size of an atom on the periodic table?
the atoms get bigger as we proceed down or to the left in the periodic table
- This would make francium (Fr) the biggest element on the periodic table and helium (He) the smallest element on the periodic table
What is the size of anions and cations compared their coresponding element?
Anion > Element > Cation
What is the trend of first ionization energy on the periodic table?
the ionization energy gets bigger as we proceed up or to the right of the periodic table
- The smaller the atom the higher the first
ionization energy
- This means that He would have the highest
ionization energy on the periodic table and Fr
would have the lowest ionization energy on
the periodic table.
What is the trend of electronegativity on the periodic table?
Highest = Fluorine
2nd highest = Cl, O
3rd highest = Br, N, S
lower values = C, H, etc
- Atoms that are closest to a Noble gas
electronic configuration (aka Halogens) are generally the most electronegative
What are quantum numbers?
n, l, ml, ms
- Each quantum number describes a different feature of the electron. (So four
numbers = four features)
What does the quantum number “n” mean?
- n” is the principle quantum number (they start with 1,2,3….)
- Planck’s quantum energy levels that correspond to increasing “shell” distances from the nucleus
What does quantum number “l” mean?
“angular momentum quantum number”
- This corresponds to the “shape” of an
orbital, or “orbital type
- “l” cannot be negative and it cannot equal the first quantum number, “n”
What are the different values for quantum number “l” and what do they mean?
There are only four different “l” values:
“l” = 0 equals an “s”(spherical) orbital.
“l” = 1 equals a “p” orbital (“pi-shaped”).
“l” = 2 equals a “d” orbital.
“l” = 3 equals an “f” orbital.
What does quantum number “ml” mean?
“magnetic quantum number”
An “l =0” value (“s” orbital) can only have an “ml” value equal 0 (-0 or +0 = 0 !).
Therefore there is only one kind of “s” orbital.
An “l” =1 value (“p” orbital) can have “ml” values of -1, 0, +1. So there are three kinds of
“p” orbitals.
An “l” = 2 value (“d” orbital) can have “ml” values of -2, -1, 0, +1, +2. So there are five
kinds of “d” orbitals.
An “l” = 3 value (“f” orbital) can have “ml” values of -3, -2, -1, 0, +1, +2, +3. So there are
seven kinds of “f” orbitals.
What does quantum number “ms” mean?
“ms” is the fourth quantum number and is related to the magnetic properties of an
electron. It’s called “spin”
It only two values here: - ½ and + ½ (usually written as +-1/2
Where (at what quantum level) do each of these n orbitals first appear?
When “n” = 1, “l” can only be = “0” i.e. an “s” orbital. At level 1 we only have an “s”
orbital!
When “n” = 2, “l” can be either “0” or “1” i.e. an “s” orbital or “p” orbitals (one “s”
orbital, three possible “p” orbitals)
When “n” = 3. “l” can be either “0”, or “1” or “2” i.e. “s” or “p” or “d” orbitals-
(one “s” orbital, three “p” orbitals, five possible “d” orbitals)
When “n” = 4. “l” can be either “0”, or “1” or “2” or “3” i.e. “s” or “p” or “d” or “f”
orbitals- (one “s” orbital, three “p” orbitals, five “d” orbitals, and seven possible “f”
orbitals).
Are all the quantum numbers equally important to understanding the underlying chemistry of that element?
The first two numbers are really important (and easy to follow) since they tell us what was the last orbital filled and therefore where we are in the periodic table.
Examples:
(4,0, x,x) = a “4s” orbital (K or Ca)
(3,2,x,x) = a “3d” orbital (an element somewhere between Sc and Zn)
What is wavelength?
symbol = “λ”, lambda
- The distance between two peaks
- Usually measured in “nm” (remember that 10^9 nm = 1 m)
Equations to find wavelength:
- Ephoton =hν = hc/λ or λ = hc/ ΔE
- λ ν = c
What energy level and light is Lyman series?
energy level = 1
light = ultraviolet (UV)
What energy level and light is Balmer series?
energy level = 2
light = visible light (300nm - 700nm)
What energy level and light is Paschen series?
energy level = 3
light = infrared light (IR)
What is the equation to find energy of hydrogen?
E = -kZ^2/n^2
-k = rydberg’s constant for hydrogen
Z = atomic number
n = energy level
Equation to calculate wavelength?
λ = hc/ ΔE
ΔE = change in energy (ΔE = Efinal - Einitial)
h = planck’s constant (6.626 x10^-34 (Joule x sec)/ photon )
v = frequency
c = speed of light (2.998 x 10^8 m/s)
λ = wavelength ( in m, NOT nm)
How to find moles of energy?
Emole = Ephoton x No
No = 6.022 x10^23 photons/mole
Bohr equation?
∆E = E(final) –E(initial) = -R[1/n2 (final)- 1/n2 (initial)]
R = 2.179 x 10^-18 J/photon
