Chem #2 Flashcards
what are the A elements?
representative elements: IA-VIIIA
• Valence electrons in either s or p subshells
this does not have to do with side of the metalloid ladder (just d or p block)
what are the B elements?
nonrepresentative elements includes:
• The Transition elements: valence electrons in s and d subshells (these are the elements in the d block)
• And the Lanthanide and actinide series: valence electrons in s and f subshells
this does not have to do with side of the metalloid ladder (just d or p block)
metals
left side and middle of the periodic table
o Active metals, transition metals, and lanthanide and actinide series
o Lustrous: shiny solids (except mercury which is a liquid under standard conditions)
o Malleability: ability to be hammered into shapes
o Ductility: pulled or drawn into wires
o Atomic level:
Low EN (high electropositivity)
Low effective nuclear charge
o Transition metals have two or more oxidation states (charges when forming bonds with other atoms)
o Conductors: due to valence electrons only being loosely held, they are free to move.
o Want to give up electrons.
what type of elements are lustrous, malleable, ductile, and good conductors?
metals
nonmetals
found predominately on the upper right side of the periodic table
o Brittle in the solid state with little or no metallic luster
o High IE, EA, and EN
o Poor conductors of heat and electricity
o Inability to give up electrons
what elements want to give up electrons?
metals
what elements want to gain electrons
nonmetals
metalloids
share characteristics with both
o Stairstep pattern that separates the metals from the nonmetals.
o B, Si, Ge, As, Sb. Te, Po, At
effective nuclear charge
a measure of the net positive charge experienced by the outermost (valence) electrons.
• Electrons between the valence e and the nucleus can mitigate the pull a little (shielding)
electrons are held _____ tightly further away from the nucleus
less
effective nuclear charge does what down a group?
stays relatively the same, more positive charge, but pulling on electrons that are in a further shell.
noble/inert gases
very stable, Group VIIIA or Group 18
atomic radius
o Atomic radius (AR): equal to ½ the distance between the centers of two atoms of an element that are briefly in contact with each other (size of a neutral element)
As you move left to right, more protons and neutrons being added, greater pull on the electrons that are being added to the same principal energy level, decreases AR
Move down, valence electrons are put into shells that are further away from the nucleus (greater energy levels), less pull, increase AR
ionic radii
Metals: lose electrons and become positive
• Will have smaller AR
Nonmetals: gain electrons and become negative
• Will have larger AR
Metalloids: depends on which side of metalloid line they fall.
NOTE: elements that are further from the ideal configuration will have more drastic changes to their AR (have to add or lose more electrons to reach this configuration)
what happens to atomic radius as you move left to right and top to bottom?
left to right: decrease
top to bottom: increase
cations have ____ atomic radius while anions have _____
smaller
larger
ionization energy
the energy required to remove an electron from a gaseous species.
o Endothermic process: requires input of heat
o Increases the closer valence electrons are held to the nucleus.
o Subsequent removal of electrons (IE2, IE3) requires even more energy.
o First ionization energy: energy necessary to remove the first electron
o Second ionization energy: energy to remove the second electron
o Active metals: elements in groups IA and IIA, such low ionization energies.
if the ionization energy is huge, probably means the element was in a ____
noble gas state
is the second ionization energy always greater than the first?
yes
is ionization energy an exothermic or endothermic process?
endothermic
ionization energy ______ up and to the right of the periodic table
increases
electron affinity
the energy dissipated by a gaseous species when it gains an electron.
o Exothermic: process expels energy in the form of heat.
AE is recorded as a positive number, heat released, but the ΔHrxn is negative.
o The stronger the electrostatic pull (greater the Zeff), the greater the energy release will be when the atom gains the electron.
o Noble gases have close to 0 electron affinity.
electron affinity is endothermic or exothermic
electron affinity is expressed as a ____ number
exothermic
positive
electron affinity ____ up and to the right
increases
The stronger the electrostatic pull (greater the Zeff), the ____ the energy release will be when the atom gains the electron.
greater
electronegativity
a measure of the attractive force that an atom will exert on an electron in a chemical bond. The greater the EN of an atom, the greater it attracts electrons within a bond.
o Higher EN, higher IE.
o Pauling electronegativity scale: scale used to express EN
electronegativity ____ up and to the right of the periodic table
up and to the right
alkali metals
(Group 1): possess most of the classical physical properties of metals, except that their densities are lower than those of other metals
o One loosely bound e- in outermost shell
o Low IE, low EN, low EA, large AR.
alkaline earth metals
share characteristics with alkali metals, but slightly higher Zeff, so smaller AR.
o Possess 2 loosely bound e- in outermost valence shell.
chalcogens
(VIA): oxygen group: nonmetals and metalloids
o Crucial for biological functions
o 6 e- in their valence shells
o Elements toward the bottom of the periodic table in this group are toxic
halogens
• Halogens (VIIA): Cl group: highly reactive nonmetals
o 7 valence electrons
o REALLY want one more e- to fill octet, very reactive
o At standard conditions, can be gaseous (F2 and Cl2) to liquid (Br2) to solid (I2).
o Halides: halogens as ion (normal)
o High EN and EA.
noble gases, inert gases
filled valence shell so minimal reactivity
o High IE, low EA, He, Ne and Ar have no EN
o Extremely low boiling points and exist as gasses at RT.
transition metals
(B, groups 3-12): metals
o Low EA, low IE, low EN
o Hard, high melting and boiling points.
o Malleable and good conductors
o Key characteristic:
Multiple possible oxidation states: represents the number of electrons that an atom can gain, lose, or share when chemically bonding with an atom of another element.
• Due to losing different # electrons from the s- and d- orbitals in their valence shells.
• Many ionic compounds
• Different color based on oxidation state
• Act as cofactors for enzymes
Complex ions:
• With water: CuSO4 x 5H20 or with nonmetals: Co(NH3)6Cl3
• Formation of complexes splits the d orbitals into 2
Leads to different solubility
o Complementary color: we observe the color that is not absorbed, the complementary of the color that was absorbed.
Subtraction frequencies: this color minus this color makes us interpret one color.
• A useful means of predicting the ultimate color appearance of an object if the color of the incident light and the pigments are known.
the electron affinity for a noble gas is ___
0
oxidation state
represents the number of electrons that an atom can gain, lose, or share when chemically bonding with an atom of another element.
complementary color
we observe the color that is not absorbed, the complementary of the color that was absorbed.
periodic law
the chemical and physical properties of elements are dependent, in a periodic way, upon their atomic numbers
which metal is a liquid under standard conditions?
mercury
______ (metals or nonmetals) have high melting points
metals
which metal has a very low density
lithium
malleability
the ability of metal to be hammered into shapes
ductility
the ability of metal to be pulled or drawn into wires
electropositivity
Electropositivity is the measure of the ability of elements (mainly metals) to donate electrons to form positive ions.
removing an electron from an atom requires an input of _____ so it is an _______ process
heat
endothermic
active metals
Groups 1 and 2 because they are so ready to lose an electron or two to obtain the stable octet.
the first ionization energy is always _____ than the second ionization energy
smaller
what is the name of a common scale used to describe electronegativity values?
Pauling electronegativity scale
For electronegativity, H goes in between the elements ___ and _____
B and C
The electronegativity value of Neon is very ______
low
which chemical group reacts violently with water and air
alkali metals
halogen phases: at standard conditions, F2 and Cl2 are _____, Br2 is ____, and I2 is _____
gaseous
liquid
solid
noble gases EN, AR, and IE
very high IE, close to 0 EA, and first 3 noble gases have negligible EN because they do not typically form bonds
noble gases are also known as _____
inert gases
what is one unique property about transition metals?
they can have different oxidations states which makes them very useful in certain biological systems
transition metals have the ability to form ____ which causes the ____ to split into two energy sublevels and absorb ____
complexes
d orbitals
certain frequencies of light
draw the color wheel
red orange yellow green blue purple
second ionization energy is always ____ than the first ionization energy for an element
greater
does the number of valence electrons influence the atomic radius of an element?
yes, moving to the right in the periodic table adds valence electrons and thus influences effective nuclear charge and atomic radius
are alkali metals or alkaline earth metals better conductors?
alkali metals
Effective nuclear charge: can look at # of protons and # of neutrons and see the ratio
ss
What is the principal quantum number of the 3d subshell?
3
