General Chemistry 1 Final
periodic law
the law that states that the repeating chemical and physical properties of elements change periodically with the atomic numbers of the elements
ground state
the lowest allowable energy state of an atom
Hybridization
the mixing of several atomic orbitals to form the same total number of equivalent hybrid orbitals
Complex lewis structure issues
- Count valence electrons - Skeletal structure (bonds- all single) - fill outer atoms until step 1 total has been used - any remaining, add pairs to central atom ( if central atom needs more, relocate share from an outer atom).
Consider the following neutral electron configurations in which n has a constant value. Which configuration would belong to the element with the most negative electron affinity, Eea?
4s^2 4p^5
In the ground-state electron configuration of Fe3+, how many unpaired electrons are present?
5
How many orbitals are there in the third shell (n=3)?
9
square planar geometry
the molecular geometry of a molecule with octahedral electron geometry and two lone pairs
seesaw geometry
the molecular geometry of a molecule with trigonal bipyramidal electron geometry and one lone pair in an axial position
tetrahedral geometry
the molecular geometry of five atoms with 109.5 degree bond angles
triple bond
A chemical bond formed when atoms share three pairs of electrons Short ( tightest spring) closest to center (Higher infrared frequency)
double bond
A chemical bond formed when atoms share two pairs of electrons, medium ( tighter spring) closer to center
covalent bond
A chemical bond that involves sharing a pair of electrons between atoms in a molecule
polar covalent bond
A covalent bond in which electrons are not shared equally
Electronegativity
A measure of the ability of an atom in a chemical compound to attract electrons
trigonal planar geometry
the molecular geometry of four atoms with 120 degree bond angles in a plane
octahedral geometry
the molecular geometry of seven atoms with 90 degree bond angles
chemical gradient
the concentration of sodium its higher outside the cell than within, while the opposite is true for potassium.
electron affinity
the energy change that occurs when an electron is acquired by a neutral atom
lattice energy
the energy released when one mole of an ionic crystalline compound is formed from gaseous ions
bond energy
the energy required to break a chemical bond and form neutral isolated atoms
first ionization energy
the energy required to remove the first electron from an atom
electron geometry
the geometrical arrangement of the electron groups
valence bond theory
the idea that covalent bonds are formed when orbitals of different atoms overlap
diamagnetic columns on periodic table
the last columns in each respective group section. end of each block
electron configuration
the arrangement of electrons in the orbitals of an atom
How many electrons should be shown in the Lewis symbol for hydrogen?
1
O
1s^2 2s^2 2p^4 - filled
Give the complete ground-state electron configuration for silicon (Si).
1s^2 2s^2 2p^6 3s^2 3p^2
Give the actual ground-state electron configuration for copper (Cu) using the complete form.
1s^2 2s^2 2p^6 3s^2 3p^6 3d^10 4s^1
20 Ca
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2
paramagnetic
Atom or substance containing unpaired electrons and is consequently attracted by a magnet.
Bond length is the distance between the centers of two bonded atoms. On the potential energy curve, the bond length is the internuclear distance between the two atoms when the potential energy of the system reaches its lowest value. Given that the atomic radii of H and F are 25.0 pm and 72.0 pm , respectively, predict the bond length of the HF molecule.
Bond length = 97.0 pm
H2
Both hydrogens bring in one electron, each H fills up a 1s^2 duet.
In the molecule BrI, which atom is the negative pole?
Br
NaF - 910 Lattice E CaO - 3414 lattice E CaO has a higher lattice energy, why?
CaO has a bigger charge ( +2) so it has bigger numbers
ionic bonding
Chemical bonding that results from the electrical attraction between cations and anions
What is the reaction that corresponds to the electron affinity of chlorine, Cl?
Cl(g)+e−→Cl−(g)
Place the following elements in order of decreasing atomic size: bismuth, bromine, neon, cesium, barium, and arsenic.
Cs, Ba, Bi, As, Br, Ne
The corner of the periodic table containing O,F,S, and Cl
F has the highest electron affinity, S has the lowest because it is furthest away from fluorine
F 9+p 9e- ---> F- 9+p 10e-
F- 9+p 10e- : repel each other, present in bigger numbers, spread out more and bigger in size
7 N
Is^2 2s^2 2p^3 - filled
K: 19p 19e- or K+: 19p 18e-? which is better
K+: 19p 18e- is better. because the ion is. pulled in harder towards the center which means a smaller radius. closer to nucleus the strong the ion.
Is orbital
Lowest energy orbital
Polarity
Molecules having uneven distribution of charges
What is the reaction that corresponds to the first ionization energy of sodium, Na?
Na(g)→Na+(g)+e−
Compound NaF vs. CaO
NaF contains N which is +1 CaO contains Ca which is +2 ( more attractive to negative things)
Dimitri Mendeleev
Russian scientist that created the perodic table according to atomic mass ( modern day periodic table)
second ionization energy
The energy needed to knock off the second valence electron.
orbital shape
The shape of an electron density distribution determined by an orbital.
Short cut for electron configuration
Use the previous noble gas ( before chosen element) then fill in the rest of the orbitals at the end ex - Te 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^10 4p^6 5s^2 4d^10 5p^4 or [Kr] 5s^2 4d^10 5p^4 (short cut)
who does VSEPR stand for?
Valence Shell Electron Pair Repulsion
Give the ground-state electron configuration for copper (Cu) using noble-gas shorthand.
[Ar]3d^10 4s^1
Give the ground-state electron configuration for silicon (Si) using noble-gas shorthand.
[Ne]3s^2 3p^2
nonpolar covalent bond
a covalent bond in which the electrons are shared equally by the two atoms
single bond
a covalent bond in which two atoms share one pair of electrons, longer (loose spring) further from center (lower infrared frequency)
bonding orbitals
a molecular orbital that can be occupied by two electrons of a covalent bond
Anti-bonding orbital
a molecular orbital that is higher in energy than any of the atomic orbitals from which it was formed
periodic property
a property of an element that is predictable based on an element's position in the periodic table
molecular orbital theory
a theory that accounts for the allowed states for electrons in molecules
First column of periodic table
alkali metals, exothermic, ions with a similar charge ( +1), Chemical reactivities are similar
diamagnetic
all electrons are paired. no attraction in external magnetic field
octet rule
atoms react by gaining or losing electrons so as to acquire the stable electron structure of a noble gas, usually eight valence electrons
Ionic
attract each other through opposite charge metal( positive ions, give e-) --> nonmetal ( negative ion, takes e-) low ---> high electronegativity
Pairs _______ when adding until more than five
cancel
Carbon monoxide (CO) is used as a purifying gas in Mond's process to produce nickel from its ores. What type of bonding occurs between the atoms of a CO molecule?
covalent
Dipole
created by equal but opposite charges that are separated by a short distance, one side is bigger or heavier
Rare gases (noble gases)
don worry about an extra electron, don't worry about bonding
F -> F+e- ion
downhill reaction, releases energy to surrounding, delta H is very negative (losing an electron)
Enter the electron configuration for the ion most likely formed by phosphorus.
electron configuration P ion: 1s^2 2s^2 2p^6 3s^2 3p^6
paramagnetic columns
every other column except. the ones at the end of each block
- charge
gains electrons
quirky exceptions to electron configuration
half-full Or al full sub levels = lower energy + add stability ex - 24 Co - [Ar] 4s^2 3d^9 steals electron for 4s orbital to make 3d orbital full ........ [Ar] 4s^1 3d^10
velence electrons
he number of electrons relation to the columns that the element is in. ex. - O has 6 valence electrons and is in the 6th column N has 5 valence electron and is in the 5th column
size of atoms
how far out electrons spread
duet rule
hydrogen forms stable molecules where it shares two electrons
What type of bonding occurs in magnesium oxide, MgO?
ionic
3 kinds of bonding
ionic, covalent, metallic
+ charge
loses electrons
What type of bonding occurs in a sample of pure cobalt, Co? In other words, how is one cobalt atom held to another cobalt atom?
metallic
bottom left hand corner of the periodic table
most metallic, low ionization energy, big radius, For easy +1 ions (loses an electron)
noble gasses
most stable. really hard to disrupt super stable electrons (Kj/Mol)
Sharing
not always equal, uneven sharing is normal
preferred geometry of a molecule
one in which the electron groups have the maximum separation ( and therefore the maximum energy) possible
lone pairs
pairs of valence electrons that are not involved in covalent bond formation
ionization energy is related to ____________ ions electron affinity is related to _____________ ions
positive, negative
Top right hand corner of the periodic table
small radius. less metallic
Positive = _____________ ions Negative=______________ions
smaller, larger
VSEPR theory
states that repulsion between the sets of valence-level electrons surrounding an atom causes these sets to be oriented as far apart as possible
thew more matched pairs, the _______ the elements is
stronger
Trigonal Bipyramidal geometry
the molecular geometry of six atoms with 120 degree bond angles between the three equatorial electron groups and 90 degree bond angles between the two axial electron groups and the trigonal plane
linear geometry
the molecular geometry of three atoms with a 180 degree bond angle due to the repulsion of two electron groups
bond order
the number of shared electron pairs between two atoms
Positive ion
the radius on a positive ion is smaller in comparison to the radius of a neutral ion
as you go down the periodic table diagonally to the left....
there is a more lousy electron affinity
Nervse Signal transmissions
tiny pumps in the membranes of your cells are working hard to transport ions-especially Sodium (Na+) and Potassium (K+) through those membranes
Mendeleev left hole in the periodic table
to predict more elements to fill the space
Which atoms draw electrons toward themselves most strongly?
upper right hand corner
Starting with Fluorine.....
very negative electrons
no loners when paired
weaker