Chemistry Test 2

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For degenerate orbitals, the lowest energy state is attained when the number of electrons with the same spin is maximized. So for a degenerate set of orbitals, one electron goes into each orbital until all the orbitals of the subshell are half-filled. Once all the orbitals of the subshell are half-filled the pairing of electrons can take place.

Hund's rule

transferred

IN AN IONIC BOND, the electron is essentially _______________ from one atom to another atom

the metal transfers its valence electrons to the nonmetal

In Ionic Bonding

polar

In general, the greater the electronegativity difference between the bonding atoms, the more ______ the bond.

terminal (at the ends)

In lewis structures, Hydrogen atoms are always _________

the energy ordering of the orbitals. Hydrogen atoms: Energy of orbital only depends on n (3s, 3p, 3d orbitals) all have the same energy (degenerate) Orbitals within a principle of a multi- electron atom: are no degenerate- energy relies on l within a principal level. Thus given value of n: E(s orbital)<E(p orbital)<E(d orbital)<E(f orbital) (THE LOWER VALUE OF L WITHIN A PRINCIPAL LEVEL, THE LOWER THE ENERGY OF ORBITAL)

What is the major difference to the Shrodinger equation for multi-electron atoms compared to the orbitals for the hydrogen atoms

no two electrons in an atom can have the same four quantum numbers, each orbital can have a max of only 2 electrons with opposing spin

What is The Pauli Exclusion Principle?

same shape, 2s larger in size and has more nodes

2s vs 1s

4p

3p or 4p farther from nucleus

the 4d, 5d, 6d, etc orbitals are similar in shape to the 3d orbitals, but they contain additional nodes and are progressively larger in size

5,5,6 d orbitals vs 3d

Bohr model: in lowest energy state, electron had this radius QM model: electron at various radii, 52.9 had greatest probability

52.9 pm

probability distribution map that shows where the electron is likely to be found

What is a quantum mechanical orbital

the future path of an electron is indeterminate and can only be described statistically- can have probability distribution map though

What is indeterminacy- describe it in terms of electrons

single electrons interfering with themselves

What is the electron interference pattern caused by

polar covalent bond

A covalent bond in which electrons are not shared equally intermediate in nature between a pure covalent bond and an ionic bond

orbital (probability distribution map showing where the electron is likely to be found)

When the electron's position can be specified, the location has to be specified as an _________

principle (n)

Which of the following quantum numbers describes the size and energy of an orbital?

less than

With like V2+, the 4s would lose electrons before 3d because 4 is greater than 3

removal

______ of successive electrons always requires more energy (e.g., Ei3>Ei2>Ei1) because a negative electron is being removed for a successively higher positive charge.

100% (although even the most ionic bonds do not reach this ideal

a bond in which an electron is completely transferred from one atom to another would have a ________ ionic character

the relative quantities of each element in a compound

a chemical formula, in combination with the molar masses of its constituent elements, indicates ___________

orbital diagram

a diagram that shows the distribution of electrons in the orbitals of the energy levels

Main group elements: Valence electrons is group number polyatomic ion: add one electron for each negative charge and subtract one electron for each positive charge

How to determine electrons for Lewis structures

bonding pair lone pair (nonbonding electrons)

a shared pair of electrons is called a _________ whereas a lone pair of electrons is called a _______

space-filling molecular model

atoms fill the space between each other to more closely represent our best estimates for how a molecule might appear if scaled to visible size

ratio of masses

empirical formula represents a ratio of atoms or ratio of moles of atoms, not a _______

Body's natural pain killers

endorphins

its lettered group number

except for helium, the number of valence electrons for any main group element is equal to _____

He : stable because n=1 quantum level fills with only 2 electrons

exception to lewis structure : helium

Cr: 4s13d5 Cu: 4s13d10

exceptions of electron configurations

boron: smaller ionization energy than beryllium (caused by the change in going from the s block to the p block)

exceptions to ionization energy?

sharing or transfer of electrons to attain stable electron configurations for the bonding atoms

in the lewis model, a chemical bond is the _________________

terminal, central

in the lewis structures, put the more electronegative elements in the _______position and less electronegative elements in the _________ position

n (principal quantum number) l (angular momentum quantum number) ml (magnetic quantum number) ms (spin quantum number)

n? l? ml? ms?

naming compounds

nomenclature

represents the radius of an atom when it is not bonded to another atom

non bonding radius (van der Waals radius)

which depicts neighboring atoms sharing some or all of their valence electrons in order to attain octets

the Lewis structure represents covalent bonding...

magnitude

the ______ of the potential energy depends inversely on the separation of charged particles

count towards the octet of both atoms double bond- when two atoms share electron pairs (stronger) the double bond on oxygen explains why its a diatomic molecule

the additional bonding pairs____

atomic radii

the approximate bond length of any two covalently bonded atoms is the sum of their ______

the orientation of an electron's spin

the arrows in an orbital diagram represent_____

all electrons in outermost shell and any partially filled D of F sub-shells

valence electrons

l = 0, s l = 1, p l = 2, d l = 3, f

value of l / letter designation

entirely new substance results

when two or more elements combine to form a compound, an ________________

nodes

where the wave function, probability density (wave function squared), and radial distribution function all go through 0 probabilty of finding an electron at a node is _______

angular (l)

which quantum number describes shape of orbital

they are held the most loosely and therefore easiest to lose or share

why are valence electrons important for chemical properties

because 4s orbitals more efficiently penetrate into the region occupied by core electrons

why do 4s orbital fill before 3d orbitals

they are instrumental in bonding because they are held the most loosely (easiest to lose or share)

why do the chemical properties of an element depend on valence electrons?

lowest

electrons generally occupy the __________ energy orbitals available

90

electrons have a ______ percent chance of being in the different estimated orbitals

THE FIRST ELEMENT

emit the mono if there is only one atom of

core electrons

electrons in complete principal energy levels and those in complete d and f sublevels

in grams

ALWAYS REMEMBER the chemical formula gives us the relationship between the amounts(in moles) of substances , not between the masses (_________) of them

increase

According to Coulomb's law, the attraction between a nucleus and an electron _______ with increasing magnitude of nuclear charge.

True

An orbital that penetrates into the region occupied by core electrons is less shielded from nuclear charge than an orbital that does not penetrate and therefore has a higher energy

cation

As electrons are removed from an atom, the remaining electrons are pulled closer to the positively charged nucleus. Conversely, if electrons are added to an atom, the nucleus becomes less efficient in attracting a larger number of electrons. For a given atom, which species would likely have the smallest radius?

Trajectory is determined by position, velocity, and forces acting on the thing. So, we cannot know an electrons trajectory (no position or velocity can be observed together)

Can trajectory of an electron be measured? Why?

lower, charged

Chemical bonds form because they ____ the potential energy of the _____ particles that compose atoms.

random

Chemical formulas indicate the ratios of the different types of atoms in a compound. Percentage composition indicates the relative masses of each element in a compound. Mass ratios are important for lab work, and atomic ratios are important for understanding chemical reactions.

valence electrons

Chemicals in the same column have the same chemical properties because they have the same number of...

all electrons in inner energy levels including completely filled D and F sub-shells

Core elecrons

do not efficiently shield one another from nuclear charge

Core electrons efficiently shield electrons in the outermost principal energy level (highest n) from nuclear charge, but outermost electrons _______________

minimizes

electrons with parallel spins have correlated motion that ______their mutual repulsion

Paramagnetic a substance that has unpaired electrons a substance that is attracted to an external magnetic field

Diamagnetic: a substance has no magnetic moment a substance has only paired electrons a substance that is weakly repelled by an external metal field

wave (wave nature most clearly seen in diffraction)

Electrons that were thought of only as particles also have ______ nature

it is easiest to remove electrons from alkali metals

First ionization energy for Alkali metals is the lowest meaning

ionization energy is already stable- requires significant energy to remove electron

First ionization energy for noble gases is highest because

Francium is the least electronegative element (most electropositive)

Fluorine is the most electronegative element

not release energy

For noble gases, the electron affinities are greater than zero because they are already stable for a noble gas, adding an electron does ___________

transition elements valence electrons

For transition elements: we also count the outermost d electrons among the valence electrons even though they are not in the outermost principle energy level

He+ H more energy to remove the 1s electron from helium because it is attracted to the nucleus by a 2+ charge, whereas H is attracted to the nucleus by a 1+ charge. therefore the electron in helium is held more tightly (lower PE)- making it more difficult to remove and making helium atom smaller than hydrogen atom

H vs He

an interference pattern similar to that of light is observed behind the slits.. The detectors between the 2 slits detect a large number of electrons. Moving outward, the detectors alternately detect small number of electrons then small numbers again, forming interference patterns characteristic of waves

How do electrons behave if an electron beam is aimed at two closely spaced slits and detectors are set up to observe the electrons after they pass through

3,2,1 The number of electrons gained corresponds to the negative charge on the ion.

How many electrons must an atom of As, Se, and Br gain, respectively, to have a total of eight valence electrons?

1,2,3 The number of electrons lost corresponds to the positive charge on the ion.

How many electrons must an atom of K, Ca, and Ga lose, respectively, to have zero valence electrons in the n=4 shell?

metallic character

How much an element acts like a characteristic metal.

K loses its electron- leaves it with no valence electrons but an octet in the previous principal energy level Cl gains an electron and forms an octet So K+ and Cl- written as KCl

Ionic bonding : K and Cl

first: remove one core electron second: rewrite EC with the removed electron and remove more electrons (requires more energy to remove core electron than valence) third: write the EC with the two lost electrons, lose another

Ionization energy when in terms of first/second/third ionization energy

As you move to the right across a row in the periodic table, the n level stays the same. However, the nuclear charge increases and the amount of shielding stays the same because the number of inner electrons stays the same. So the effective nuclear charge experienced by the electrons in the outermost principal energy level increases, resulting in a stronger attraction between the outermost electrons and the nucleus and, therefore, smaller atomic radii..

KNOW THIS

When certain combinations form an octet or not

Lewis structure accounts for why particular combination of atoms form molecules and other do not

0

Metals lose electrons to achieve noble-gas configuration. If the valence shell is considered to be n=4, how many valence electrons are in a stable ion of a period 4 metal?

lose

Metals tend to ______ their valence electrons in a chemical change to attain noble gas configuration

g CO2 - mol CO2 - Co2 molecules

Molar Mass

systems with high PE tend to change in ways that lower their potential energy and systems with low PE tend to not change- they are stable. Because atoms with 8 electrons have particularly low PE, the noble gases are stable and they cannot lower their energy by reacting with other atoms/molecules

Noble gases?

8

Nonmetals gain electrons to achieve noble-gas configuration. How many valence electrons are in a stable nonmetal ion?

when we try to observe the hole the electron goes through (particle) we lose the interference pattern (wave) and vice versa

Observation rules?

principle level

Orbitals with the same value of n are in the same

noble gas configuration

elements without _______________ react to attend a _________-

When an atom becomes an ion, additional electrons shield the nuclear charge, whereas fewer electrons strengthen the attraction between the nucleus and the electrons. Therefore, the ionic radius is larger than the atomic radius for the same element when it becomes an anion, and the ionic radius is smaller than the atomic radius when it becomes a cation. When comparing two elements with the same electron configuration, whether an atom and an ion or two ions, the element with fewer protons will have the larger radius because it has a weaker nuclear charge.

RULE

as we move down a column in the periodic table, the principal quantum number (n) of the electrons in the outermost principal energy level increases, resulting in larger orbitals and therefore larger atomic radii as we move to the right across the4 periodic table, the effective nuclear charge experienced by the electrons in the outermost principal energy level increases, resulting in a stronger attraction between the outermost electrons in the nucleus and smaller atomic radii

SUMMARY OF TRENDS

H(wave function symbol) = E(wave function symbol H is total energy of the electron within the atom, E is energy of the electron, wave function symbol describes the wavelike nature of the electron wave function squared = orbital (probability distribution)

Schrodinger equation ( energies and orbital of electron)

the amount of energy required to remove the second electron from an already POSITIVE ion from a gaseous ion

Second ionization energy?

lattice that energy is emitted as heat when the lattice forms

Since the sodium ions are positively charged and the chlorine atoms are negatively charged, the potential energy decreases (Columbs law) when these ions come together to form_______

electronegativity difference value

Small: Nonpolar Covalent (0-0.4) Intermediate: Pure Covalent(0.4-2.0) Large: Ionic (2.0 +)

the octet rule

States that atoms lose, gain or share electrons in order to acquire a full set of eight valence electrons

Like if two Cl Atoms pair together, they get an octet. Or if two H pair together, the one unpaired electrons come together for a duet

The Lewis structure helps explain the tendency of some electrons to form diatomic molecules

No two electrons in an atom can have the same set of four quantum numbers (n, ℓ, mℓ, and ms).

The Pauli exclusion principle:

second

The _____ IE is always greater than the first IE

Energy

The __________ determines the frequency and wavelength of the photon

increase

The anions will experience a smaller effective nuclear charge, which results in an _____ in ionic radius.

Electrons are added to the lowest energy orbitals available.

The aufbau principle

Single electron traveling through space has wave nature- wavelength is related to Kinetic Energy. The faster the electron is moving, the higher the Kinetic Energy and the shorter its wavelength.

The de Broglie Wavelength

the electronegativity difference between 2 bonding atoms

The degree of polarity in a chemical bond depends on ...

psoitive

The effective nuclear charge experienced by an atom's outermost electrons continues to become more________ as we move to the right across across the rest of the second row, resulting in successively smaller atomic radii. The same trend is observed for most main group elements

(Delta)E= -2.18 x 10^-18J(1/n^2-1f/n^2i)

The equation for the change in energy that occurs in an atom when an electron changes energy levels

heat (the process is exothermic)

The formation of an ionic compound from its constituent elements usually gives off quite a bit of energy as ________

smallest whole number ratio of ions

The formula of an ionic compound reflects the __________

Emmited light

The greater the difference between the principal quantum numbers (n) involved in the electron transition (to the same ground state), the greater the frequency of the ______

the attraction between two covalently bonded atoms is due to sharing one or more electron pairs in the space between them- thus each bond links just one specific pair of atoms in contrast to ionic bonds which are nondirectional and hold together an entire array of ions- thus the fundamental units of molecules can react with each other in many different ways

The lewis structure also accounts for why covalent bonds are highly directional

Energy

The more we know about position, the less we know about ______. And vice versa (complementary properties)

maximum number

The number of columns in a block corresponds to the _______ maximum number of electrons that can occupy a particular sublevel of that block

smaller

The smaller the magnitude of the charge separation, and the smaller the distance between charges, the _______ the dipole moment

1+

The valence electron in lithium experiences the 3+ charge of the nucleus through the shield of the 2- charge of the core electrons. The effective nuclear charge acting on the valence electron is approx _______

1 find atomic number to figure out number of electrons 2 distribute electrons 3 S: ONE P: THREE D: FIVE F: SEVEN

To write an electron configuration

higher in frequency and therefore shorter in wavelength than transitions between orbitals that are closer in energy

Transitions between orbitals that are further apart in energy produce light that is __________________

except for helium, the number of valence electrons for any main group element is equal to its lettered group number ( row number of MGE is equal to n number)

Valence electron row rule

the valence electrons are those in the outermost principal energy level (highest n)

Valence electrons for main group elements

Complimentary properties: the more we know about one the less we know about the other- in quantum mechanics the observation of an event effects the outcome

Wave and Particle nature are...

To melt the solid, forces must be overcome, which requiresa significant amount of heat model counts for in conductivity- does not account for electricity except for predicting the conduct electricity

We model an ionic solid as lattice of individual ions held by forces that are not directional (as we move away from the center of the ion, the forces are equally strong in all directions) what does this say about melting?

the name of the polyatomic ion whenever it occurs

We name ionic compounds in the same way we name other ionic compounds except we incorporate _______

The wave nature of the electron is an inherent property of individual electrons. In this case, the unobserved electron goes through both slits- it exists in two states simultaneously- and interferes with itself. EXPLAINS EXISTENCE OF STATIONARY STATES and prevents electtons from crashing into nucleus

What can be concluded from the fact that: electrons come out of the source singly and we can record where each electron stikes the detector after it has passed the slits. We record the position of thousands of individual electrons and fine the same interference pattern

The particular orbitals that electrons occupy for that atom

What does an electron configuration show?

an electron particle traveling through a single slit with no interference pattern (observing factors forces an electron into one state and only can go through one slit)

What does an experiment designed to observe the electron traveling through the slits?

the orientation of the orbital -1 to 1. ( if l=3, ml values could be -3,-2,-1,0,1,2,3)

What does ml determine?

elements with three of fewer valence electrons

What elements are more likely to lose electrons

The light flashes near the slit the electron comes out of and the interference pattern goes away- WE CAN NEVER SEE BOTH SEE THE INTERFERENCE PATTERN AND simultaneously DETERMINE WHICH HOLE ELECTRON GOES THROUGH

What happens when a laser beam is placed directly behind the slits?

potential energy (E) of 2 charged particles depends on their charges (q1 and q2) and on their separation (r) like charges attract, opposite charges repel

What is Colombs law

when filling degenerate orbitals electrons fill them singly first: reflects atoms tendency to find the lowest energy state possible

What is Hund's rule

Linus Pauling, The Nature of the Chemical Bond

electronegativity was quantified by American chemist

alkali: 1+ alkaline: 2+ halogens: 1-

alkali, alkaline, halogens trend?

gain

all nonmetals tend to ______ electrons when they undergo chemical changes to attain noble gas configurations

first

always need more energy to remove the second electron rather than the ____ because we remove electrons ,the resulting ion becomes more positive, so it requires more energy to remove a negative electron from an increasingly positive ion

paramagnetic

an atom or an ion that contains unpaired electrons is attracted to an external magnetic field , and we say that atom is ______

diamagnetic

an atom or an ion which all electrons are paired is not attracted to an external magnetic field- it is instead slightly repelled- and we say it is ______

valence electrons

an atom's _______________- are the most important in chemical bonding

THE COMPLEMENTARITY OF THE WAVE NATURE AND PARTICLE NATURE OF THE ELECTRON RESULTS IN THE COMPLEMENTARITY OF VELOCITY AND POSITION

an electron is observed as wither a wave or a particle never both- explain

anions: _____ the number of electrons indicated by the magnitude of the charge of the anion (-charge) cations:______ the number of electrons indicated by the magnitude of the charge transition metal cation: we remove the electrons in the highest n value orbitals first

anions, cations, transition metal cations?

no- in quantum mechanics trajectories are replaced with probability distribution maps

are electrons deterministic (present determines the future)

helps explain the transition metal cation trend

as discussed previously, the ns and (n-1)d orbitals are extremely close in energy and depending on the exact configuration, can vary in relative energy ordering as the (n-1)d orbitals begin to fill in the first transition series, the increasing nuclear charge stabilizes the (n-1)d orbitals relative to the ns orbitals. This happens because the (n-1)d orbitals are not the outermost (or highest n) orbitals and are therefore not effectively shielded from the increasing nuclear charge by the ns orbitals

Zeff decreases and the ionic radius becomes larger.

as more electrons are added, what happens to Zeff?

Zeff increases and the ionic radius becomes smaller

as more electrons are removed, what happens to Zeff?

decreases

as you move away from the nucleus (center of plot), the probability density _______

1. as we move down a column (or family) in the periodic table, the atomic radius increases 2. as we move to the right across a period (or row) in the periodic table, the atomic radius decreases

atomic radii trends

a set of average bonding radii determined from measurements on a large number of elements and compounds it represents the radius of an atom when it is bonded to another atom and is always smaller than the VanderWalts radius

atomic radius

most atoms contain many electrons occupying a number of different orbitals (all orbitals in ballon(atom))

atoms are usually drawn in spheres because________

valence

electrons farthest from the nucleus

because electrons occupy the lowest energy orbitals available when the electrons are at ground state, only 2 electrons w opposite signs are allowed in each orbital

aufbau principle - this pattern of orbital filling

decreases Li much bigger than Li+ CATIONS ARE MUCH SMALLER THAN THEIR CORRESPONDING NEUTRAL ATOMS

because the outermost electron is shielding by the core electrons, it makes up a lot of the size of the atom, so when an anion loses this electron ,the size majorly _______

nonmetals: one half the distance between two of the atoms bonded together metals: one half the distance between two of the atoms next to each other in a crystal of the metal

bonding atomic radius (covalent radius)

- explain how atoms bond together to form molecules - exbalins why some atoms are stable and others are not - predict shapes of molecules

bonding theories?

we can get a sense of the degree to which the electron is transferred (or the degree to which the bond is ionic)

by comparing the actual dipole moment of a bond to what the dipole moment would be if the electron were completely transferred from one atom to another...

the force that hold atoms together in a compound result of interactions between charged particles (electrons and protons)

chemical bond?

they lower the potential energy between the charged particles that compose atoms

chemical bonds form because

- the quickest and easiest way to represent a compound - indicates the elements present in the compound and the relative number of atoms/ions in each

chemical formula?

first

chemical formulas usually list the more metallic (positively charged) elements _______

the unknown compound undergoes combustion (or burning) in the presence of pure oxygen

combustion analysis (way to obtain empirical formulas)

binary compounds

contain only two different elements.

molecules, molecular compounds

covalently bonded atoms form ______, and the resulting compounds are called ________

change in energy

delta E = Efinal-Einitial

the same

each subsequent row, the highest principal quantum number increases by one as we move down the column, the number of electrons in the outermost principal energy level (highest n value) remains ______

actual nuclear charge (Z) minus the charge shielded by other electrons (S)

effective nuclear charge

negative/exothermic because energy is generally released when an electrons is added the attraction between the nucleus of an atom and the incoming electron usually results in the release of energy as the electron is gained

electron affinity is generally ______

one electron does not have more or less spin than the other spin up: 1/2 spin down: -1/2

electron spin (ms)?

the ability of an atom to attract electrons to itself in a chemical bond (which results in polar and ionic bonds) in HF, we would say fluorine is more electronegative than hydrogen because it takes a greater share of the electron density in HF

electronegativity

the larger the atom, the less ability it has to attract electrons in a chemical bond

electronegativity is inversely related to atomic size...

decreases

first ionization energy generally _______as we move down a column (or family) in the periodic table because electrons in the outermost principal level are increasingly farther away from the positively charged nucleus and therefore held less tightly

increases

first ionization energy generally _____as we move to the right across a row in the periodic table because the electrons in the outermost principal energy level generally experience a greater effective nuclear charge. this means electrons feel a higher and higher positive charge , attracting more to the nucleus as we go right. Meaning it requires more energy to sperate the negative and positive charges.

the outermost principle energy level (highest n value)

for MAIN GROUP electrons: the valence electrons are those inb ______

electrons in the outermost principal level are farther away from the positively charged nucleus- and are therefore held less tightly- as we move down the column...THIS RESULTS IN LOWER IONIZATION ENERGIES AS WE MOVE DOWN THE COLUMN

for a given sublevel, orbitals with higher principal quantum number is bigger than orbitals with smaller principal quantum number (4s larger than 3s), which means....

larger o2- much bigger than o

for an anion, there is one additional outermost electron but no additional proton to increase the nuclear charge, so the extra electron increases the repulsion among the outermost electron making the anions much ________ than their corresponding neutral atoms

less

for group 1A metals, electron affinity becomes _______ exothermic as we move down the row

2 vowels

for molecular compounds, if a prefix ends in a or o, drop it to avoid ________

minus 2

for the f block, the principal quantum number of the f orbitals fill across each row number _______

(number of atoms in 1st element in chemical formula x atomic mass of 1st element) + (number of atoms of 2nd element in chemical formula x atomic mass of 2nd element)

formula mass =

alkali metals ns^1 one electron beyond a noble gas, so they often lose the ns^1 electron to form an ion with 1+ charge in their reactions

group 1A elements?

alkaline earth metals ns^2 tend to lose ns^2 electron to form a 2+ charge in their reactions

group 2A elements?

halogens ns^2Np^5 one electron short of noble gas, to to gain electron in reactions with metal to form ions with 1- charge

group 7A elements?

the number of sublevels in any level is equal to n, so n=1 is 1 sublevel, n=2 is 2 sublevel

how are sublevels and n related

name of cation (metal) + charge of cation (metal) in roman numerals + ide

how do you name a binary ionic compound containing a metal that forms more than one type of cation

name of the cation (metal) + base name of the anion (nonmetal) + ide

how do you name a binary ionic compound containing a metal that forms only one type of cation

prefix-name of 1st element-prefix-base name of 2nd element plus ide the first element is more metal-like (the one more towards the left and bottom of the PT) generally we write the name of the element with the smallest group number first (if they lie in the same group, we write the element with the greatest row number 1st)

how to name molecular compounds

contain a specific number of water molecules associated with each formula unit hemi: 1/2-octa 8

hydrates - H2O

effective nuclear charge

if one electron comes toward the lithium ion: (3+ from the nuclus and 2- from the electrons for a net charge of +1)

core

if were removing one core and one electron, it should require more energy to remove a _____ electron

equal

in a chemical formula, the sum of the charges of the anions must be __________ to the sum of the charges of the cations

elements combine in fixed, definite proportions whereas a in a mixture, elements can mix in any proportion

in a compound,

dipole moment

in a covalent bond: electrons are shared between atoms in a polar covalent bond: electrons are shared unequally- electrons spend more time near one atom then the other (creates _______)

dots surrounding the abbreviation of the element

in a lewis structure we represent the valenc electrons of main group elements as _______

single location- always moving

in an orbital, the electron does not have a _____

the same combination of elements may form several different molecular compounds each with a different formula

in contrast to an ionic compound, the formula for a molecular compound cannot always be determined from its constituent elements because ...

between every two atoms the place to terminal, then to central giving octet (duets for H) if any atoms lack an octet, form double or triple bonds from lone pairs on terminal atoms

in lewis structures, where do electrons go first

small is a covalent bond ELECTRONS TRANSFERRED

intermediate electronegativity difference (like 2 nonmetals): polar covalent bond (partial negative on the more electronegative atom and a partial positive on the less electronegative atom) ELECTRONS SHARED UNEQUALLY

1. metal forms only one type of ion (always same charge)- main group metals 2. metal forms more than one type of ion (charge can differ)- transition metals usually

ionic compound: metal and non mental 2 sections?

positive and negative ion

ionic compounds always contain___________

charge neutral

ionic compounds must be

positive

ionization energy is always ________ because removing an electron always takes energy

the amount of energy required to remove an electron for a gaseous electron or ion (they are endothermic because it requires energy ti remove an electron)

ionization energy?

more

it requires significantly _____ energy to remove a core electron than a valence electron

The successive ionization energies for valence electrons in an atom are increasing but not dramatic. Once those valence electrons are removed, the next electron removed is from a previously filled inner shell. This ionization is much more difficult, energetically, and this is where the "jump" occurs. Since Li has one valence electron, the "jump" will occur between the 1st and 2nd ionization energies. N has five valence electrons and the "jump" will occur between the 5th and 6th ionization energies. Be has two valence electrons and the "jump" will occur between the 2nd and 3rd ionization energies. S has six valence electrons and the "jump" will occur between the 6th and 7th ionization energies.

jumps with valence electrons?

ionic ELECTRONS SHARED EQUALLY

large electronegativity difference between two atoms (like metals and nonmetals), the electron from the metal is almost completely transferred to the nonmetal, and the bond is _______

de Broglie reaction

mass times velocity is momentum- electron inversely proportional to momentum VELOCITY IS RELATED TO WAVELENGTH

lose electrons gain electrons so, when a metal interacts with a nonmetal, it can transfer one or more of its electrons to the nonmetal. the metal then becomes a CATION (positively charged atom) and the non metal becomes a ANION (negatively charged atom)

metals have a tendency to: nonmetals have a tendency to:

lose

metals tend to ______ electrons when they undergo chemical changes

two or more nonmetals

molecular compounds are....

within, between molecular compounds tend to have a lower melting and boiling point than ionic compunds

molecular compounds have strong covalent bonds _______ molecules and weak intermolecular forces _______ molecules

n = molecular mass / empirical formula mass

molecular formula = empirical formula x n where n=1,2,3 molar mass = empirical formula molar mass x n

formula mass

molecular mass and molecular weight are the same as

molecular model

more accurate and complete way to specify a compound atoms as balls and chemical bonds as sticks

polar

more electronegative, more ______

OCTET

most stable compound

En=-2.18 x 10^-18J(1/n^2) The energy is negative because the electron's energy is lowered by its interaction with the nucleus The orbitals- as n increases, energy increases (less negative) as n increases, the spacing between the energy levels become smaller

n energy?

ionization energies (their electrons are relatively difficult to remove) So, when a nonmetal bonds with another nonmetal, neither atom transfers electron to the other. Instead, the two atoms share electrons. The shared electrons interact with the nuclei of the bonding atoms, lowering the PE.

nonmetals tend to have a higher _____________

constant

number of electrons in outermost level remains

mass percent composition

one way to express how much of an element is in a given compound is to use the elements ____________

chemical bonds

only noble gases contain full outer principal quantum levels. because the rest of these elements do not posses the stability of the noble gases, they form ______ to become more stable. (to lower the PE of the charges particles)

sublevel

orbitals with the same value of n and l are in the same An atomic orbital, or collection of atomic orbitals, that occupy a principal energy level and are called s, p, d, and f.

ic represents greater charge (III)

ous indicates lesser charge (II)

electrons beyond the noble gas configuration that precedes the noble gas

outer electron configuration: inner electron configuration:

ClO - HYPOchlorITE ClO2- chlorITE ClO3- chlorATE ClO 4- PERchlorATE

oxyanion naming?

Anions containing oxygen and another element (most common polyatomic ion)

oxyanions

octet

particularly stable because they have a full outer principal level- easily identified because they have 8 dots

As the outer electron undergoes penetration into the region occupied by the inner electrons, it experiences a greater nuclear charge and therefore (coulombs law- lower energy (bc negative electron to positive nucleus)

penetration rule

the ratio of a bond's actual dipole moment to the dipole moment it would have if the electron were completely transferred from one atom to the other, multiplied by 100 percent

percent ionic character

having a positive pole and a negative pole

polar

an ion composed of 2 or more atoms

polyatomic ions

polar covalent

pure covalent and ionic are two extremes-- most covalent bonds between dissimilar atoms are actually ________, somewhere between the two extremes

represents the total probability of of finding the electron within a thin spherical shell at a distance r from the nucleus - not probability density at point r, but total probability at a radius r - probability has maximum at nucleus, where RDF has zero at nucleus

radial distribution function

S: 1 p: 2 d: 4 f: 8

shapes pf orbitals:

a fraction ...x/100 or 100/x you can use this as a conversion factor

since percent means per hundered, we can also write mass percent composition as:

shared electrons in a covalent chemical bond hold the bonding atoms together by attracting the positive charges of their nuclei

stability of covalent bonds:

properties

structure determines ______

1. lower energy orbitals fill before higher energy orbitals: 1s 2s 2p 3p 4s 3d 4p 5s 4d 5p 6s 2 orbitals can hold no more than 2 electrons each- spin is opposite in same orbital- another way of expressing Pauli exclusion principle 3 when orbitals of identical energy are available, electrons first occupy the orbital singly with parallel spins rather than in pairs (hunds Rule)

summarize orbital filling

roughly constant

the atomic radii of the transition elements _____ follow the same trend as the main group elements as we move to the right across the row instead of decreasing in size, the radii of the transition elements stay ________ across each row

formula mass

the average mass of a molecule (or formula unit) of a compound is a ___________

formula unit or the smallest, electrically neutral collection of ions exists as a larger lattice

the basic unit of an ionic compound is the __________

An ionic bond

the bond that forms between a metal and a nonmetal is _________

covalent bond

the bond that forms between two nonmetals is a _____

lattice energy

the energy associated with the formation of a cystaline lattice of alternating cations and anios from the gaseous ions.

Delta E atom = -E photon

the energy carries a negative sign because the atom emits energy as it relaxes from n=3 to n=2

electron affinity

the energy change associated with the gaining of an electron by the atom in the gaseous state. Electron affinity, EA, is the energy required to add an electron to a neutral gaseous atom and is related to an element's position on the periodic table.

ionization energy (IE)

the energy required to remove an electron from the atom or ion in the gaseous state

second ionization energy, third ionization energy notice that the second ionization energy is not the energy required to remove 2 electrons from Na, but rather the energy required to remove 1 electron from Na+

the energy required to remove the second electron, the third electron

smaller bc 16+ pulling on 18 electrons is a bigger atomic radius than 20+ pulling on 18 electrons

the greater the nuclear charge in atoms or ions withthe same number of electrons, the _______ the atom

outermost electrons

the key connection between the macroscopic world (elements chemical properties) and the particulate world (atom's electronic structures) lies in the __________

valence electrons are dots lewis structures are molecules GOOD FOR MAKING PREDICTIONS ABOUT MOST MOLECULES

the lewis model

chemical bonding involves the transfer of sharing valence electrons between 2 or more atoms

the lewis model focuses on valence electrons because...

upside down u = qr

the magnitude of a dipole moment created by separating two particles of equal but opposite charge of magnitude q by a distance r is given by the equation

that element's percentage of the compound's total mass

the mass percent composition or mass percent of an element is...

the mass in grams of 1 mol of its molecules or formula units--is numerically equivalent to its formula mass formula mass:amu molar mass:g/mol

the molar mass of a compound

noble gases (8A)

the most unreactive elements in the entire periodic table

columns

the number of ______ in a block corresponds to the maximum number of electrons that can occupy the particular sublevel of that block

n^2 so n=3 level has 9 orbitals

the number of orbitals in any level is equal to what

2l + 1 p sublevel l=1, has 3 orbitals

the number of orbitals in any sublevel is equal to what

no bond is 100 percent ionic. in general, bonds with greater than 50 percent ionic characters are referred to as ionic bonds

the percent ionic character generally increases as the electronegativity difference increases, however we can see....

the row number minus one

the principal quantum number of the d orbitals that fill across each row in the transition series is equal to ______

the highest n

the row number of the main group elements is equal to________

covalent bonds

the shared electrons are chemical _______

phase

the sign of the amplitude of a wave is known as the ______

attract one another and form an ionic compound, which in the solid state is composed of a lattice (a regular three dimensional array of alternating cation and anions)

these oppositely charged ions...

three shared electron pairs very strong- hard to break- un reactive molecule explains why Nitrogen is a diatomic molecule

triple bonds

we cannot simultaneously measure an electrons position and wavelength with infinite precision (more accurately you know the position less accurately you know the velocity- Heisenberg's uncertainty principle)-

velocity: related to wave nature position: related to particle nature- particles have well defined positions and waves do not what does this mean?

the probability of finding that electron in space (probability over unit volume)

wave function squared is the probability density which is...

relative number of atoms of each element in a compound actual number of atoms of each element uses lines to represent covalent bonds and shows how atoms in a molecule are connected or bonded to each other empirical formula for hydrogen peroxide: HO LEAST INFO molecular formula: H2O2 structural formula: H-O-O-H MOST INFO

we categorize chemical formulas into 3 different types empirical formulat: molecular formula: structural formula:

dash

we often represent a bonding pair of electrons by a ____ to emphasize the pair constitutes a chemical bond

a dipole moment (upside down u) occurs anytime there is a speration of positive and negative charge

we quantify the polarity of a bond bu the size of its dipole moment

transition level ions

we remove the ns electrons before the (n-1)d electrons when writing configurations for ________

in complete principal energy levels and those in complete d and f sublevels

what are core electrons

s and p blocks

what are the main group elements

1. Potential energy (E) associated with the interaction of like charge is positive but decreases at particles get farther apart. Since systems tend toward lower PR, like charges that are close together have high PE but tend to move away from one another to lower PE LIKE CHARGES REPEL 2. The potential energy (E) associated with the interaction of unlike charges is negative and becomes more negative as particles get closer together. Since systems tend toward lower PE, the interaction of unlike charges draws them closer together (toward lower PE) UNLIKE CHARGES ATTRACT ONE ANOTHER 3. The magnitude of the interaction between charged particles increases as the charges of the particle increase. (an electron eith a charge of 1- is more strongly attached to a nucleus of 2+ rather than 1+)

what are the three important conclusions from colombs law

d and f blocks

what are the transition elements

sublevel energy splitting

what determines the order of orbital filling within a level

The shape of the orbital - can be 0 to (n-1)

what does l determine?

the orientation of the spin of the electron.

what does ms determine?

the overall size and energy of an orbital

what does n determine?

the total probability of finding the electron within the spherical shell at a disance r from the nucleus

what does the radial distribution function for an atomic orbital show

for multi electron atoms, any single electron experiences both positive charge of nucleus (attractive) and negative charges of other electrons (repulsive). Repulison of one electron by other electrons is screening or shielding that electron from the full effecgts of nuclear charge

what is shielding

spacial distributions pf electrons within a sublevel

what is the energy splitting a result of

the result of multiplying 1. the probability density function(wave function squared) (probability divided by unit volume). The PDF has a maximum at the nucleus and decreases with increasing r 2. the volume of the thin shell ( 0 at the nucleus, increases with r increasing)

what is the shape of the radial distribution

inward pull of the nucleus on the electrons in the outermost principal energy level (highest n)

what is the trend in the atomic radius based on

as we move down a column, n of the valence electrons increases and the valence electrons occupy larger orbitals

what results in larger atoms (atomic radii trends)

particularly low

when a quantum level is completely full, the overall potential energy of the electrons that occupy that level is ______

excited or promoted to a higher energy orbital. However this makes the atom unstable, and it quickly flies back or relaxes to a lower energy level (as it does it releases a photon of light containing an amount of energy equal to the energy difference of the two energy levels)

when an atom absorbs energy, an electron in a lower energy orbital is ________-

low

when an outer principal quantum level is particularly low, the overall potential energy of electrons that occupy that level is particularly ____

removal

when there is a big jump in ionization energy, this means _______ of an electron There is generally a large jump in ionization energy (IE) between the valence electrons of an element and its core electrons.

if these interactions lead to an overall net reduction of potential energy between charged particles, a chemical bond forms covalent vs ionic depending on the atoms

when two atoms face each other: - electrons go towards nucleus - electrons repel electrons - nucleus repels nucleus


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