Quantum Numbers
For an electron in the n= 4 energy level: what are the possible values of l?
l= 3,2,1,0
Draw the condsesed electron configuration for Cu
[Ar]4s^1 3d^10
What is the periodic table trend for atomic size?
Down a group: increase
Across a period: decrease
Ionic bonding is the (blank) of electrons and is observed when a (blank) bonds to a (blank)
Ionic bonding is the TRANSFER of electrons and is observed when a METAL bonds to a NONMETAL
Which bond is shorter:
C-O or C=O
why?
C=O
why: double bonds involve more sharing of electrons, which oulls the atoms closer together
given the l value of 2. Find the possble values for ml.
ml= -2,-1, 0,1,2
Define diamagnetic and paramagnetic
Diamagnetic: a species with all of its electrons paired and is NOT attracted by a magnetic field (ex. Zn)
paramagnetic: a species with one or more unpaired electron and IS attracted by a magnetic field (ex. O)
consider Ionic size, do cation become smaller or larger than their neutral atoms?
Smaller- the loss of electrons leads to reducuded electron repulsion
When do ionic compounds conduct electricity?
Melted or dissolved; the ions are free to move and carry a current (NOT IN THE SOLID STATE)
How many bonding pairs and lone pairs are on the central atom of NH3?
bonded: 3
lone: 1
give the name for the quantum number:
n= 4, l=2
4d
n=4
l=2(since d corresponds to l=2)
what is an isoelectronic species?
give an example
Species with the same electron configuration
example: F-, Na+, Mg2+ all have the same configuration (1s^2 2s^2 2p^6)
Rank in order of most negative to least negative electron affinity:
O, N,F,Cl, Br
F>Cl>O>Br>N
Definition: The energy released when an atom gais an electron to form an anion
Trend: EA becomes more negative across a period and less negative down a group
F have the most negative EA meaning it gains an electron most easily
What is the trend for lattice energy?
Across a period: Increases
Down a group: decreases
when do metals conduct electricity
in solid form (delocalized electrons in the metal move more freely)
what would be the shape of the following orbitals
-2s
- 1p
2s: sphere
1p: dumbell
Draw the condensed electron configuration for Cr. Then determine the inner, outer, and valance electrons
[Ar]4s^1 3d^5
inner: 18
outer: 1
Valence: 6
which of the following has the highest ionization energy?
Ne, Ar, Kr, Xe
Ne (noble gases have the highest IE because they have a stbale octet and resist losing electrons)
Does SrO or MgO have a higher lattice energy?
SrO
why: same charges, but Sr is bigger than Mg so the bond distance is greater in SrO (weaker electrostatic force)
determine the type of bond based on the difference in electronegativity
Cl-Cl
nonpolar covalent
Given the 5f orbital, find the value of n, l, and ml
n= 5
l= 3 (since f corresponds to l=3)
ml= -3,-2,-1,0,1,2,3
Draw the condesed configuration for Se. Then determine the inner, outer, and valence electrons. Is is paramagnetic or diamagnetic. If paramagnetic how many unpaired electrons are there?
[Ar] 4s^2 3d^10 4p^4
inner: 18
outer: 6
valence: 6
paramagnetic (2 unpaired electrons)
Rank the elements from increasing ionic size:
Na+, Al3+, Mg2+
Na+>Mg2+>Al3+
What has a higher melting point MgO or KCl
MgO
why: Mg and O have higher charges, so they have a stronger attraction, which makes for a higher melting point
Which bond is more polar:
C-O or C-H
C-O
why: the electronegativity difference ins larger