General Chemistry- The Periodic Table Flashcards
1
Q
What atomic number is lithium (Li)?
A
3
2
Q
What type of element is Lithium?
A
Soft Alkali metal
3
Q
What are the specific characteristics of lithium?
A
Least dense solid element (specific gravity .53)
Does not naturally occur on earth in its elemental form
Found only in various salt compounds
4
Q
Which chemist published the 1st periodic table? When?
A
Dmitri Mendeleev in 1869
5
Q
What did Dmitri Mendeleev find?
A
Ordering known elements according to atomic weight revealed a pattern of periodically recurring physical and chemical properties.
6
Q
Who has revised the periodic table?
A
Henry Moseley
7
Q
How did Henry Moseley revise the periodic table?
A
Organized the elements based on increasing atomic number rather than atomic weight
8
Q
What did the revision to the periodic table allow?
A
Elements to be predicted and discovered
9
Q
The periodic table creates a visual representation of what?
A
The periodic law
10
Q
What is the periodic law?
A
The chemical and physical properties of the elements are dependent, in a periodic way, upon their atomic number
11
Q
How is the periodic table arranged?
A
Arranged elements into periods (rows) and groups/families (columns)
12
Q
How many periods does the periodic table have?
A
7 periods
13
Q
What do the periods represent?
A
The principal quantum numbers n=1 through n=7 for the s and p block elements
14
Q
What do groups contain?
A
Elements that have the same electronic configuration in their valence shell and share similar cchemical properties.
15
Q
The elements are recorded how, in the periodic table?
A
In their neutral state
16
Q
What do the roman numerals represent?
A
The number of valence electrons elements in that group have in their neutral state.
17
Q
What are “A” elements known as?
A
The representative elements
18
Q
“A” elements have their valence electrons in which orbitals?
A
S or p subshells
19
Q
What are “B” elements known as?
A
Nonrepresentative elements
20
Q
Which groups are associated with “B” elements?
A
The transitions elements
Lanthanide and actinide series
21
Q
Where are the valence electrons for “B” elements for transition elements and lanthanide/actinide elements?
A
Transition elements: s and d subhsells
Lanthanide/Actinide: s and f subshells
22
Q
Which elements may have unexpected electron configurations?
A
The nonrepresentative elements
23
Q
Examples of unexpected electron configurations?
A
Chromium (4s1 3d5)
Copper (4s1 3d10)
24
Q
Which identification system are the elements not listed under A and B?
A
IUPAC
Groups are number 1 to 18
25
Mendeleev's table was arranged by atomic weight, but the moder periodic table is arranged by...
Atomic number
26
What are the three categroies of the periodic table?
Metals
Nonmentals
Metalloids (semimetals)
27
Where are the metals found on the periodic table?
The left side and in the middle of the periodic table
28
What do the 3 categroies of metals include?
Active metals
Transitions metals
Lanthanide and actinide series
29
What are the characteristic of metals?
Lustrous (shiny) solids
High melting point and densities
Malleability
Ductility
30
What are the exceptions to some of the characteristic of metals?
Mercury- not lustrous
| Lithium- Not high density
31
What is the definition of malleability?
The ability of metal to be hammered into shapes
32
What is the definition of ductility?
Ability to be pulled or drawn into wires
33
How is a metal defined?
A low effective nuclear charge, low electronegativity (high electron positivity), large atomic radius, small ionic radius, low ionization energy and low electron affinity.
34
What causes the manifestation of the characteristics of metals?
The ability of metals to easily give up electrons
35
The transitions metals have how many oxidation states?
2 states
36
What are oxidation states?
Changes when forming bonds with other atoms.
37
Due to loose valence electrons in metals what are metals good at?
Conductors of heat and electricity
38
Active metals are found in which subshell?
s subshell
39
Transitional metals are found in which subshells?
s and d subshells
40
Lanthanide/Actinide metals are found in which subshells?
s and f subshells
41
Which transition metals are not reactive?
Copper, nickel, silver, gold palladium, platinum
42
The nonreactive transition metals are good for what type of production?
Coins
| Jewelery
43
Where are nonmetals found on the periodic table?
Predominantly on the upper right side of the periodic table.
44
What are the characterisitic of nonmetals?
```
Generally brittle in the solid state
Little or no Metallic luster
High ionization energies
Electron affinities
Electronegativities
Small atomic Radii
Large ionic radii
Poor condiuctors of heat and electricity
```
45
The manifestation of the characteristic in nonmetals results due to what?
Inability of nonmetals to easily give up electrons
46
Compare nonmetals and metals, which are less unified? what properies?
Nonmetals are less unified in
Chemical
Physical properities
47
Where are metalloids on the periodic table?
Separating the metals and nonmetals
48
What is another name for metalloids?
Semimetals
49
Why are they called semimetals?
They share some characteristics with both metals and nonmetals.
50
What are the characteristics of metalloids?
Electronegativities and ionization energies lie between metals and nonmetals
Density, Melting poind, Boiling point vary widely
Combination of metallic and nonmetallic characteristics
51
Which elements are considered metalloids?
```
Boron (B)
Silicon (Si)
Germanium (Ge)
Arsenic (As)
Antimony (Sb)
Tellurium (Te)
Polonium (Po)
Astatine (At)
```
52
Which elements are debated over whether they are included as metalloids?
Polonium
| Astatine
53
How many key rules are there that control how valence electrons work?
3
54
What is the 1st key rule?
For elements in the same period, effective nuclear charge (Zeff) increase from left to right
55
What is the explanation of the 1st key rule?
As one moves across a period from left to right, electrons and protons are added one at a time. Positivity of the nucleus increase, and the electrons experience a stronger electrostatic pull toward the center of the atom. This causes the electron cloud to move closer and bind more tightly to the nucleus.
56
What is the definition of effective nuclear charge?
Electrostatic attraction between the valence shell electrons and the nucleus, which is a measure of the net positive charge experienced by the outermost elecctrons.
57
How is the pull from the nucleus to the valence electrons mitigated?
Nonvalence electrons that reside closer to the nucleus.
58
How is effective nuclear charge shown, in elements of the same period on the periodic table?
Increasing (Zeff) from left to right
59
What is the second key rule?
As one moves down a group, (Zeff) is remained constant, but valence electrons are held less tightly to the nucelus
60
What is an explanation of the second key rule?
As one moves down the group, the rpincipal quantum number increases by one each time. The valence electrons are increasily separated from the nucleus by a greater number of filled principle energy levels. This separation leads to a reduction in the electrostatic attraction between the valence electrons and the nucleus. Thus, the increasing shielding created by the inner shell electrons cancels the increased positivity of the nucleaus. So, (Zeff) stays constant, while valence electrons are held less tightly.
61
How is the 2nd key rule seen on the periodic table?
As you move down a group, (Zeff) is constant, while Valence electrons are more likely to react or leave an element.
62
What is the 3rd key rule?
Elements can gain or lose electrons in order to achieve a stable octet formation representative of the novle (inert) gases (Group ViiiA or 18) or the Octet Rule.
63
Which elements are stable following the octet rule?
Elements that have biological roles
64
Why is the octet rule not necessarily a rule?
Many exceptions to the rule.
65
What is the atomic radius?
Equal to one-half of the distance between the centers of two atoms of an element that are briefly in contact with each other.
66
How do you measure the atomic radius?
Measure the distance between two atoms of the same element and divide that distance by two.
67
Why can't the radius be measured by examining a single atom?
The electrons are constatly moving around making it impossible to mark the outer boudary of the electron cloud.
68
From left to right on the periodic table, how does the (Zeff) change?
Increases
69
How does atomic radius change on a periodic table from left to right?
Decreases
70
How does the Atomic radius changed down a group on the periodic table?
Increases down a group
71
Where will the largest atom be in a group?
At the bottom
72
Where will the largest atom be in a period?
Group IA or Group 1
73
Which atom has the largest atomic radius?
Cesium
74
Which atom has the smallest atomic radius?
Helium
75
Why is Francium not considered as having the largest atomic radius?
It is exceptionally rare in nature
76
What are the two generalizations made to understand atomic radii?
Metals lose electrons and become positive
Nonmetals gain electrons and become negative
Metalloids can go in either direction, but tend to follow the trend based on which side of the metalloid line they fall.
77
How are the ionic generalizations inferred on the MCAT?
Information found in passages and questions, such as oxidation states in compounds
78
For nonmetals close to the metalloid line, their group number dictates what?
They require more electrons than other nonmetals to achieve the electronic configuration seen in group VIIIA
79
Nonmetals do _______ while the nuclei does __________.
Nonmetals gain electrons while the nuclei maintains the same charge.
80
What ionic radius do nonmetals close to the metalloid line possess, compared to the ionic radius of elements closer to group VIIIA?
Closer to metalloid line possess a larger ionic radius than those closer to group VIIIA
81
Metals are _______ in regards to their ionic radius compared to nonmetals.
Opposite
82
Metals closer to the metalloid line have ________ to achieve the electronic configuration seen in group VIIIA.
To lose more electrons
83
Metals closer to the metalloid line have _________ ionic radius compared to other metals.
Smaller
84
Why do metals in group IA have less reduction in radius during ionization?
Have fewer electrons to lose, thus they have a less drastic reduction in radius during ionization
85
What is ionization energy (IE)?
The energy required to remove an electron from a gaseous species.
86
What is another name for ionization energy?
Ionization potential
87
What is an endothermic process?
Requiring an input of heat
88
What is the explanation for increased ionization energy?
The greater the atom's (Zeff) or the closer the vlaence electrons are to the nucleus, the more tightly bound they are. This makes it more difficult to remove one or more electrons, increasing the ionization energy.
89
How can the change in ionization energy be seen on the periodic table?
Ionization energy increases from left to right and bottom to top
90
What is First Ionization Energy?
The energy necessary to remove the first electron
91
What is Second Ionization Energy?
The energy necessary to remove the second electron from the univalent cation (X+) to form the divalent cation (X2+)
92
What are active metals?
Low ionization energy metals or metals in groups IA and IIA (groups 1 and 2)
93
What are two examples of active metals?
Lithium and Beryllium
94
Active metals do not _______.
Exist naturally in their neutral forms
95
How many electrons need to be lost in order to form stable valence shells for alkali and alkaline metals?
One electron for Alkali
| Two electrons for Alkaline earth metals
96
Which elements rarely give up electrons?
Halogens (Group VIIA or Group 17)
97
How are the values for second ionization energy for group IA, Group IIA, and Subsequent monovalent cations?
Disproportionally larger for group IA
| Not that much larger for Group IIA or subsequent monovalent cations
98
Which elements are the least likely to give up electrons?
Noble gases or inert gases
99
Which elements have the highest ionization energy?
Noble gases
100
Why is the second ionization so much larger for goup IA?
Because Group IA already lost their one valence electron making them have a noble gas like electron configuration. Pulling a second valence electron out is like trying to pull an electron out of a noble gas.
101
Which group is most likely to accept electrons?
Halogens
102
Why are Halogen's so greedy with electrons?
By aquiring one additional electron, a halogen is able to complete its octet and achieve a noble gas configuration.
103
What is an exothermic process?
Expelling energy in the form of heat
104
What is electron Affinity?
The energy dissipated by a gaseous species when it gains an electron
105
What is electron affinity the opposite of?
Ionization energy
106
Why does (Change in (Hrxn)) have a negative sign?
Because it is an exothermic process
107
How is electron affinity reported?
As a positive number because it is the energy dissipated
108
What is the units of electron affinity?
KJ/mol
109
What causes a greater energy release, in regards to electron affinity?
The stronger the electrostatic pull (the higher the (Zeff) between the nucleus and the valence shell electrons, the greater the energy release when the atom gains the electron.
110
How is the change in electron Affinity shown on the periodic table?
Increases across the period from left to right
| Decreases from top to bottom.
111
Which groups have a very low electron affinity?
Group IA and IIA (group 1 and 2)
112
Which group has a very high electron affinity?
Group VIIA (Group 17)
113
Do the noble gases have high electron affinity?
No, its closer to zero
114
Why do noble gases have low electron affinities?
They already possess a stable octet and cannot readily accept electrons
115
Which has the lower electron affinities, metals, nonmentals, or metalloids?
Metals
116
What is electronegativity?
A measure of the attractive force that an atom will exert on an electron in a chemical bond.
117
The greather the electronegativity of an atom, the more ________________.
It attracts electrons within a bond
118
What are electronegativity values related to?
Ionization energies
119
The lower the electronegitivity, the ________ the _________.
Lower the ionization energy
120
What elements are exceptions to the electronegativity and ionization rule? Why?
The first three noble gases because despite their high ionization energies, these elements have negligible electronegativity because they do not often form bonds.
121
What is the most common scale to meausre electronegativity?
Pauling electronegativity scale
122
Electronegativity is what?
A relative measure
123
What is the range of the scale used to find electronegativity?
0.7 to 4.0
124
Which are the least and most electronegative elements?
Least: Cesium
Most: Flourine
125
How does electronegativity change on a periodic table?
Increase across a period from left to right
| Decreases from top to bottom
126
What are the three increaseing factors on a periodic table from left to right?
Electronegativity
Ionization energy
Electron affinity
127
What is the decreaseing factor on the periodic table from left to right?
Atomic radius
128
What are the increasing factors on a periodic table from bottom to top?
Electronegativity
Ionization energy
Electron affinity
129
What is the decreasing factor on the periodic table from bottom to top?
Atomic radius
130
Which metals are the classic physical properties of metals?
Alkali metals
131
What is the exception to the classic physical properities of metals seen in Alkali metals?
Density is lower than most metals
132
How many loosely bound electrons do the Alkali metas have in there outer most shell?
One
133
What trends are seen in Alkali metals?
```
(Zeff) values are very low
Largest atomic radii of all elements in their respective periods
Low ionization energies
Low electron affinities
Low electronegativities
```
134
Alkali metals lose one electron to form what?
Univalent cations
135
Alkali metals react with _________, especially _________.
Nonmetals especially Halogens
136
Alkaline earth metals possess what?
Many properties charateristic of metals
137
What makes Alkaline metals different from Alkali?
Slightly higher effective nuclear charges and thus slightly smaller atomic radii
138
How many valence electrons does Alkaline metals have in the outer most shell?
Two
139
What is formed when both electrons are removed from Alkaline metals?
Divalent Cations
140
Which two metal types make up Active metals? Why?
Alkali and Alkaline Earth Metals
| They are so reactive that they are not naturally found in their elemental (neutal) state.
141
What are chalcogens?
Group VIA or Group 16
| An eclectic group of nonmentals and metalloids
142
What are chalcogens crucial for?
Normal biological functions
143
Chalcogens are not as ______________________ as halogens.
Reactive
144
What are characteristics of Chalcogens?
Six electrons in their valence shell
Small atomic radii
Large ionic radii
145
Why is oxygen the most important?
It is one of the primary consituents of water, carbohydrates, and other biological molecules.
146
Why is sulfur important?
Component in amino acids, and vitamins
147
Why is selenium important?
It is a Nutrient for microorganisms
148
What is important to know about the rest of the Chalcogens?
They are primarily metallic and generally toxic
149
In high concentrations, chalcogens are what?
Toxic or damaging
150
What are halogens?
Group VIIA or 17
| Highly reactive nonmetals with seven valeence electrons
151
What are Halogens desperate to do?
Complete their octets by gaining one additional electron
152
The physical properties of halogens are what?
Variable
153
Which halogens are gaseous?
F2 and Cl2
154
Which halogens are liquid?
Br2
155
Which halogens are solid?
I2
156
What is more uniform for the halogens?
Chemical reactivity
157
Due to their high electronegativities and electron affinities, Halogens are what?
Especially reactive twoard the Alkali and Alkaline earth metals
158
Which element has the highest electronegativity?
Flourine
159
Why aren't Halogens found in their elemental state?
They are too reactive
160
What are the ions of Halogens called?
Halides
161
What is another name for noble gases?
Inert gases
162
What are noble gases?
Group VIIIA or Group 18
163
Why are noble gases also called inert gases?
They have minimal chemical reactivity due to their filled valence shells.
164
What do noble gases have in regards th their characterisitics?
High ionization energies,
Little or no tendency to gain or lose electrons
No measureable electronegativities
165
Which elements, in particular to noble gases, have no electronegativities?
He
Ne
Ar
166
What is extremely low in noble gases?
boiling point
167
At room temperatiure, what form do noble gases take?
Gas
168
How are noble gases usually seen throughout the world? Why?
As comercial lighting sources
| Their lack of reactivity
169
What are transition metals?
Groups IB to VIIIB or (Groups 3-12)
| Metals
170
What is low, in regards to characteristic in transition metals?
Electron affinities
Ionization energies
Electronegativities
171
What characteristics do transition metals have?
Very hard
High melting/boiling points
Quite malleable
Good conductors
172
Why are transition metals good conductors?
Loosely held elctrons that progressively fill the d-orbitals
173
What is a unique property of transition metals?
Many of them can have different oxidation states
174
What is an oxidation state?
Possible charged forms
175
Why can transition metals have different charged forms?
They are capable of losing different numbers of electrons from the s- and d-orbitals in their valence shells.
176
Due to the change in oxidation state of transition metals, what occurs?
Transition metals form many different ionic compounds
177
For transition metals, the oxidation states correspond to what?
Different colors
178
What are the compounds associated with each color when dealing with transition metals and their oxidation states?
```
Red: Cobalt (II) nitrate- Co(NO3)2
Orange: Potassium Dichromate- K2Cr2O7
Yellow: Potassium chromate- K2CrO4
Green: Nickel(II) chloride-NiCl2
Blue: Copper(II) sulfate- CuSO4
Violet: Potassium Permanganate- KMnO4
```
179
Complex transition metal ions tend to associate with what two molecules?
Water
| Nonmetals
180
What are complex ions associated with water called?
Hydration complexes
181
What is an example of hydration complex, associated with transition metals?
CuSO4-5 H2O
182
What is an example of a complex ion associated with a nonmetal, in regards to transition metals?
[Co(NH3)6]Cl
183
AgCl is soluable in _______, not soluable in _______.
```
Aqueous ammonia (due to the formation of the complex ion [Ag(NH3)2]+
Water
```
184
The formation of complexes, for transition metals, causes what?
The d-orbitals to split into two energy sublevels
185
The two energy sublevels of transition metals allows complexes to do what?
Enables many of the complexes to absorb certain frequencies of light
186
Which frequencies give the transition meta's complexes their characteristic color?
The frequencies not absorbed give the complexes their characteristic colors
187
What is subtraction frequencies?
Frequencies not absorbed
188
When we perceive an object as a particular color, what is it due to?
That color is not absorbed, but rather reflected by to you by the object.
189
What does our brain tend to mix when visualizing a transition metal?
The subtraction frequencies with their complementary color or the frequency absorbed.
