FINAL EXAM- Periodicity Flashcards
(37 cards)
Period
A horizontal row of elements in the periodic table.
Series
a set of elements with common properties or of compounds related in composition or structure. SAME AS PERIOD- horizontal row of elements on the periodic table
Isoelectronic
having the same numbers of electrons or the same electronic structure. Ex. F and O-1
Periodicity
the quality or character of being periodic; the tendency to recur at intervals. The periodic law states that the physical and chemical properties of the elements recur in a systematic and predictable way when the elements are arranged in order of increasing atomic number.
Ionization energy
The energy required to remove AN electron from a neutral atom (not ion) of an element in the gaseous state
Electron affinity
The energy change that occurs when an electron is acquired by a neutral atom (most atoms release energy when they acquire electrons).
Electronegativity
measure of the ability of an atom in a compound to attract electrons from another atom in a compound.
Atomic radius
One half of the distance between the center of identical atoms that are not bonded together.
Alkali metals
- Column 1 or 1A (except H)
- Shiny, soft, low density, never found in elemental state in nature, one valence electron
- Loses one VE to form an ion with a +1 charge
- Reacts easily with oxygen
- Produces hydrogen and a solution in exothermic reaction with water (produces heat, basic substance left behind- bases can be just as harful as acids)
- Will float (low density)
- Need the ion in your diet
Alkaline earth metals
- Column 2 or 2A
- Similar to alkali metals- just not as
- 2 valence electrons, loses these two valence electrons to form an ion with a +2 charge
- Not as vigorously react
- Not as shiny, soft, etc
- A little harder, more dense, etc
Halogens
- Column 7 or 17
- All nonmetals
- 7 Valence electrons
- Gains one electron to form ions with a -1 charge
- Diatomic
Nobel or Inert gases
- Column 8 or 18
- Chemically inactive, rarely form compounds
- Has 8 Valence electrons (except He which has only 2 electrons total)
- Stable
Transitional metals
- Starting in column 3 and all the way over- everything beneath the staircase excluding La, Ac, and Al
- Form ions with varying charges
- Good conductors of electricity
- Have a high luster
- Less reactive than alkali and alkaline-earth metals- some so unreactive that they exist in in nature as free, single elements.
- D-block element s
Inner transitional (rare earth) metals
- The two rows of elements at the bottom + La and Ac
- F block
- Same as transitional with varying charges
- Lanthanides and Actinides
Metalloids
- Elements that border above the periodic table plus Ge and Sb (B, Si, Ge, As, Sb, Te, and At)
- Has some characterists of metals
- Some characteristics of nonmetals
- Solids at room temperature
- Less malleable than metals
- Not as brittle as nonmetsl
- Semiconductors of electricity
Representative metals
- First two columns, minus H, plus Al
- Always loses the same amount of electrons when they lose ions
- Form ions that always have the same charge
Nonmetals
- Elements to the right of metalloids, plus H
- Opposite of metals
- Not malleable
- Not ductile
- Doesn’t conduct hear and electricity
- Many valence electrons
Lanthanide and Actinide series
- 2 different series*
- Make up the inner-transitional metals*
- Two rows of elements at the bottom
- Lanthanides is the top one
- Actinides is the bottom one
- F block elements
- Actually wedged between groups 3 and 4
- Shiny metals
- Similar in reactivity to Group 2 alkaline-earth metals
To determine sublevels (generally):
- S includes the alkali and alkaline earth metals
- P includes the nonmetals
- D includes the transition metals
- F includes the inner transition or rare earth metals
To determine charge of the common ions
- Corresponds to the column number
- Only works for columns 1, 2, and 13-18 but we still refer to 13-18 3-8
- column number for 1-3
- for number of columns away from the nobel gases for 5-7
- column 4 can be + or –
- column 8 has no charge
- Ex. Be is +2, N is -3, and Si is + or – 4
To determine number of energy levels
- Number of valence electrons=family/group/column
- Row number (horizontal)= number of energy levels
- Only works for S and P block
- D block- number of energy levels= row #(n)-1
- F block- number of energy levels= row #(n)-2
- Ex. H has one, Al has 3, Hg has 5, and Th has 5
Basically everything has to do with
columbic attraction (attraction of negatively charged electrons to the positively charged nucleus) and the size of the radius. Smaller radius= larger columbic attraction since there is a smaller distance between the nucleus and electrons (think of magnets)=easier to gain electrons. Larger radius=lower columbic attraction since there is a bigger distance between nucleus and electrons.
Ionization energy
- The energy required to remove AN electron from a neutral atom of an element in a gaseous state.
- Ionization energy increases as the atomic radius decreases (Larger radius=easier to remove electrons)
- Increases from left to right on the periodic table
Electron affinity
- The energy change that occurs when an electron is acquired by a neutral atom.
- The more nonmetallic, the higher the electron affinity
- Increases right and up on the periodic table
