final
trends of ionic radii
* an anion is larger than its parent atom * within an isoelectronic serious of cations, ionic radius decreases with increasing nucleus charge * Ionic radius increases down a group on the periodic table
What correctly describes the formation of ions by the transition metals
* most transition metals can form more than one cations * transition metals first lose electrons from the ns level when forming ions
valence electrons
--- Electrons in the outer energy level of an atom are called valence electrons. ----The number of electrons in the valence shell of an atom is equal to the group number for the main group elements. ---- these electrons are important because they are the ones that become involved in chemical reactions
angular momentum quantum number
--- The angular momentum quantum number is a quantum number that describes the 'shape' of an orbital and tells us which sub shells are present in the principal shell
Increasing wavelength
--- wavelength ---- UV radiation ---- visible light ---- IR radiation ---- Radiowaves
Quantum Numbers
---- The quantum number N indicates the principle energy levels of an orbital ---- the quantum number L indicates the shape of an orbital ----the relatives size of the orbital is indicated by the value of N
formal charge
-----When an atom does not contain the same number of atoms as that predicted by the periodic table, that atom in the molecule may possess a charge; all these charges add up to equal the charge on the molecule. ------The formal charge on an atom is equal to the number of valence electrons in a neutral, isolated atom minus the number of electrons "owned" by that atom in a molecule.
Lewis structure
---A symbolic representation of an element that shows its valence electrons as dots is known as an electron-dot structure or Lewis symbol. ---In writing Lewis symbols, put electrons around an atom before you start pairing up. ---In Lewis dot structures, two electrons are referred to as an electron pair and single electrons are unpaired electrons.
sigma and pi bonds
---Every single covalent bond is a sigma bond. ---Every double covalent bond has both a sigma and a pi bond in it. ---Every triple covalent bond has a sigma and two pi bonds in it.
single bond
1 sigma bond
double bond
1 sigma bond, 1 pi bond
triple bonds
1 sigma bond, 2 pi bonds
Group 1A: Alkali Metals (Li, Na, K, Rb, Cs, Fr). charge
1+ charge.
VSEPR model and shapes
1. linear 2. trigonal planar 3. Bent 4. Pyramidal 5. tetrahedral
Tetrahedral bond angle:
109.5°
Trigonal bond angle:
120
Linear bond angle:
180°
Molecular shapes
2 linear 3 trigonal-planar 4 tetrahedral 5 trigonal-bipyramidal 6 octahedral
Group 2A: Alkaline Earth Metals (Be, Mg, Ca, Sr, Ba, Ra) charge
2+ charge
Octahedral bond angle:
90°
Combination reaction
A + B --> AB
Single displacement
A + BC --> AC + B
triple bond
A bond formed when atoms share three pairs of electrons
covalent bond
A chemical bond that involves sharing a pair of electrons between atoms in a molecule
double bond
A covalent bond in which two pairs of electrons are shared between two atoms
molecule
A group of atoms bonded together
solvent
A liquid substance capable of dissolving other substances
Solubility
A measure of how much solute can dissolve in a given solvent at a given temperature.
Electronegativity
A measure of the ability of an atom in a chemical compound to attract electrons
anion
A negatively charged ion
Arrhenius definition of an acid
A substance that dissociates in water to produce H+ ions
solute
A substance that is dissolved in a solution.
What is the central atom of AB2
A= central atoms in molecular B2= atoms surrounding the central atom
Double displacement
AB + CD --> AD + CB
EA lower for group for 2 A than 1 A
Added electron in higher energy NP orbital, well shielded from the nucleus
EA lower for group 5 A than 4 A
Added electron placed in an already half filled NP orbital, increasing electron repulsion
a covalent compound is a compound that contains only convalent __________
Bonds
Noble gases
Completely filled valence P subshell
Why does ionization energy increase left to right across a period?
Effective nuclear charge increases and the outermost electron becomes harder to remove
ionic bond
Formed when one or more electrons are transferred from one atom to another
Chemical Equilibrium
In a chemical reaction, the state in which the rate of the forward reaction equals the rate of the reverse reaction, so that the relative concentrations of the reactants and products do not change with time.
Match each angular momentum quantum number L= 0 L= 1 L=2 L=3
L 0 = one L 1= three L 2= five L 3= seven
mendeleev's original periodic table ordered elements by atomic _________, whereas the modern periodic table is ordered by atomic ___________
Mass ; number
The more tightly an electron is held by the nucleus, the _________ difficult it is to remove and the ________ the ionization energy
More; higher
Polyatomic Ions
NH4+ ammonium PO43- phosphate CO32- carbonate NO3- nitrate CO22- carbonite NO2- nitrite PO33- phosphite SO42- sulfate OH- hydroxide SO32- sulfite HCO3- bicarbonate
What elements have the electron configuration of 1s^2 2s^2 2p^6
Na+ O2- F-
Hybrid Orbitals
Orbitals of equal energy produced by the combination of two or more orbitals on the same atom
electrolytes
Substances that release ions in water --Strong electrolytes are completely ionized in solution (70-100% dissociation). Weak electrolytes are only slightly ionized in solution
ionization energy
The amount of energy required to remove an electron from an atom
valence electrons
The number of electrons in the valence shell of an atom is equal to the group number for the main group elements.
naming acids
To name an acid with an anion ending with the -ite suffix, drop the -ite suffix and add the suffix, -ous acid
short hand notation
To reduce space required for elements with many electrons, a shorthand method is used. To use the shorthand method, first, locate the specified element in the periodic table and write the symbol of the immediately preceding noble gas in brackets. Then finish the electronic configuration.
formal charge equation
V - (1/2)B - L
VSEPR theory
VSEPR theory is based upon the idea that electron pairs in the valence shell of an atom repel one another. A molecule (or ion) will be the most stable when its electron pairs are in such a geometric position as to minimize their repulsions (i.e. the electrons try to get as far apart from one another as possible).
combustion reaction
a chemical reaction that occurs when a substance reacts with oxygen, releasing energy in the form of heat and light
single bond
a covalent bond in which two atoms share one pair of electrons
Decomposition reaction
a reaction in which a single compound breaks down to form two or more simpler substances
electron affinity increases
across a period
naming acids
anion ending with the -ate suffix, drop the -ate suffix and add the suffix, -ic acid
Group 7A: Halogens (F, Cl, Br, I, At).
charge 1-
isotopes
chemical elements that has the same chemical properties (the same atomic number) but differs in mass.
lewis structures are used to represent covalent compounds. shared electron pairs are shown either as pairs of _______ or lines and only _________ electrons are shown
dots ; valence
electron affinity varies little
down a group
the octet rule states that an atom other than hydrogen tends to form bonds until it is surrounded by _________ valence electrons
eight
Noble gases
electron is added to an (n+1) orbital. very weakly attracted to the nucleus due to shielding by the core electrons
frequancy equation
f = c / λ = wave speed c (m/s) / wavelength λ (m)
the speed of wave is determined by multiplying the ____________ of the wave by its wavelength
frequancy
main group nonmetals
gain electron to fill the np sublevel
elements that are in the same ___________ of the periodic table will have the same ____________ electron configuration and will have very similar chemical _______
group ; outer ; behavior
isoelectronic
having the same number of electrons
isoelectronic
having the same numbers of electrons or the same electronic structure.
Transition metals
incompletely filled D subshell
Lanthanides and Actinides
incompletely filled F subshell
main group elements
incompletely filled S or P subshell
The energy required for the complete removal of 1 mol of electron from 1 mol of gaseous atoms or ions is called _________ energy. For a neutral element this energy is a measure of how easily the element forms an ion with a _______ charge
ionization; positive
frequancy
is the number of waves per unit of time.
Bond ______ is defined as the distance between the nuclei of two ______ bonded atoms in a molecule
length; covalently
resonance forms
lewis structures that represent hypothetical extremes of electron arrangements in a molecule
Electron domain geometries
linear, trigonal planar, tetrahedral, trigonal bipyramidal, or octahedral.
Alkeli Metals
lose all electrons from the NS sub-level
metals in group 3 a
lose np electrons first, then the ns electrons
transition metals
lose ns electrons before losing (n-1)d electrons
For many elements on the periodic table, the ____________ number gives the N value of the highest principle energy level containing electrons. for main group elements only, the ______________ number is always equal to the number of valence electron
period ; group
cation
positively charged ion (lost electrons)
the speed of waves is the ________ of its wavelengths and frequency. As wavelength increases frequency will ___________
product; decreases
which is stronger, a sigma bond, or a pi bond?
sigma bond
aqueous solutions.
solutions in which water is the solvent
quantum numbers
specify the properties of atomic orbitals and the properties of electrons in orbitals
VSEPR theory
states that the repulsion between electron pairs causes molecular shapes to adjust so that the valence-electron pairs stay as far away as possible.
The angular momentum quantum number L indicates the ___________ of the orbitals in an atom. A value L= 0 indicates _________ type orbital while a D orbital is indicated by L value of __________
sublevels; S; 2
Arrhenius definition of a base
substance that produces OH- ions in aqueous solution
nonelectrolytes
substances that form no ions in water and cannot conduct electricity
formal charge
the charge assigned to an atom in a molecule or polyatomic ion derived from a specific set of rules
electron affinity
the energy change that occurs when an electron is acquired by a neutral atom
bond dissociation energy
the energy required to break the bond between two covalently bonded atoms
electron affinity
the first electron affinity is the energy released when 1 mole of gaseous atoms each acquire an electron to form 1 mole of gaseous -1 ions
Hybridization
the mixing of two or more atomic orbitals of silimiar energies on the same atom to produce new hybrid atomic orbitals of equal energies (describes the orbitals that contain the valence electrons)
chemical reaction
the process by which one or more substances change to produce one or more different substances
single bond
two atoms share one pair of electrons
multiple bond
two atoms share two or more pairs of electrons