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Unit 4The Periodic
Table
Know ItLove ItAmaze Your Friends
How do I write names & symbols? Spelling COUNTS!! Symbols MUST be written in BLOCK print!! Symbol’s first letter is always uppercase and
the second letter (if one) is always lowercase!!
For Example:Co Cobalt (an element)CO Carbon Monoxide
(compound of carbon and oxygen combined)
NO Scripty / Cursive A, N, H, etc...
l is a lowercase L not an uppercase I
Which elements do I have to know?
ELEMENT SYMBOLHydrogen HHelium HeLithium LiBeryllium BeBoron BCarbon CNitrogen NOxygen O
ELEMENT SYMBOL
Fluorine FNeon NeSodium NaMagnesium MgAluminum AlSilicon SiPhosphorus PSulfur S
Which elements do I have to know?
ELEMENT SYMBOL
Chlorine ClArgon ArPotassium KCalcium CaIron FeCopper CuZinc ZnBromine Br
ELEMENT SYMBOL
Silver AgTin SnIodine IGold AuMercury HgLead PbFrancium FrUranium U
Dmitri Mendeleev
Russian Chemist In 1869, he published the first periodic table. He organized the elements in a way that
would help his students learn them more easily.
He made a card game with the information known about each element listed on separate cards. They could then be arranged by the properties the elements had in common.
Mendeleev settled on an organization of elements that was based on the masses of the elements.
Mendeleev found that when the elements were arranged in order of atomic mass, many physical and chemical properties of the elements followed repeating patterns.
Worked for most elements, but not all. Three pairs of elements had to be switched,
but Mendeleev thought these masses were measured incorrectly.
Ekasilicon Mendeleev was able to accurately predict the
existence of elements not yet discovered. These showed up as gaps in his periodic table.
One such element gap, Mendeleev called ekasilicon. He predicted its mass, density, melting point and color based on its location in the periodic table.
Fifteen years after this prediction, a new element was discovered in Germany and given the name Germanium. Its properties matched the properties of ekasilicon.
H.G.J Moseley worked in Rutherford’s lab. Found that metals produce X-rays when
bombarded with energetic electrons and that the frequencies differed for each metal. These frequencies, came from differences in a fundamental property of each element; the amount of positive charge in the nucleus.
The amount of positive charge = the number of protons = the atomic number.
Modern Periodic Law
When the elements are arranged in order of increasing atomic number, their physical and chemical properties show a periodic, repeating pattern.
Periodic Table Arrangement
Periods – the horizontal rows of elements.• The modern periodic table has 7 periods.
• The period tells the number of energy levels used. This number is called the Principal Quantum Number.
Groups – the vertical columns of elements.• The modern periodic table has 18 groups.
• The “A” groups tell the number of valence electrons.
• Groups are sometimes referred to as families.
Li = 1s22s1 Na = 1s22s22p63s1
K = 1s22s22p63s23p64s1
*Li, Na, K all have 1 valence e-*All are found in group 1 or IA*Li in pd. 2 Na in pd. 3 K in pd. 4
B = 1s22s22p1 Al = 1s22s22p63s23p1
Ga = 1s22s22p63s23p64s23d104p1
*B, Al, Ga all have 3 valence e- *All are found in group 13 or IIIA
*B in pd. 2 Al in pd. 3 Ga in pd. 4
N = 1s22s22p3 P = 1s22s22p63s23p3
As = 1s22s22p63s23p64s23d104p3
*N, P, As all have 5 valence e-*All are found in group 15 or VA*N in pd. 2 P in pd. 3 As in pd. 4
F = 1s22s22p5 Cl = 1s22s22p63s23p5
Br = 1s22s22p63s23p64s23d104p5
*F, Cl, Br all have 7 valence e-*All are found in group 17 or VIIA*F in pd. 2 Cl in pd. 3 Br in pd. 4
Groups of the Periodic Table
Elements within a group on the periodic table have similar properties to each other.
This is due to the number of valence electrons. Having the same number of valence electrons makes them bond to similar atoms in the same ratios.
If you know the properties of one element in a group, you know the properties of all the elements in that group!!!
Trends of the Periodic Table
Atomic Number Atomic Mass Metal / Nonmetal Trend Atomic Radius Ionization Energy Electronegativity
Atomic Number
The number of protons in one atom of a given element.
Increases as you move down a group.
Increases as you move across a period.
Average Atomic Mass
The average mass of all the isotopes of a given element.
Increases as you move down a group.
Increases as you move across a period.
Atomic Number/Avg.Atomic Mass
increases
I n c r e a s e s
Metal / Nonmetal / Metalloid
Elements on the left side of the table are metals.
• There are 88 metals on the periodic table.
Elements on the right side are nonmetals.• There are 17 nonmetals on the periodic table.
Elements on the “staircase” between the metals and nonmetals are metalloids.
• There are 7 metalloids on the periodic table.
Properties of Metals and Nonmetals
Property Metals Nonmetals
Color Silver Not Silver
Luster Shiny Dull
Conductivity Conductor Insulator
Malleability Malleable Brittle
Reaction to Acid
Reaction to Acid
No Reaction to Acid
Electron donor or acceptor
Electron Donors
Electron Acceptors
Properties of Metalloids
Metalloids have properties of both metals and nonmetals.
For example: Silicon
Is silver, shiny and a conductor like a metal.
Is rough, brittle and has no rxn to acid like a nonmetal.
Activity Series Some metals are more reactive than others
and will replace less reactive metals during a reaction.
Li, K, Ca, Na, Mg, Al, Zn, Fe, Pb, H, Cu, Hg, AgDECREASING REACTIVITY
Will Ca replace Zn in a reaction?Yes, Ca is more reactive than Zn
Will Zn replace Mg in a reaction?No, Zn is less reactive than Mg
Metal vs. Nonmetal Trend
Nonmetals Metals Metalloids
Most Active Nonmetal
Most Active Metal
Atomic Radius
The distance from the center of an atom’s nucleus to its outermost electron.
Atomic radius increases as you move down a group on the periodic table.
• Because an electron cloud is added.
Atomic radius decreases as you move across a period on the periodic table.
• Full shells with paired-up electrons have less repulsion, so the take up less space.
Atomic Radius
Fr
Ionization Energy
The amount of energy required to remove a valence electron from an atom.
Decreases as you move down a group on the periodic table.
• More “shielding” from full electron shells.
Increases as you move across a period on the periodic table.
• More difficult to remove electrons from a full shell.
Electronegativity
The attraction for shared electrons in a chemical bond.
Decreases as you move down a group on the periodic table.
• Valence electrons get farther from the nucleus because there are more full e- shells. The attraction between the + nucleus and – electrons decreases.
Increases as you move across a period on the periodic table.
• More protons, stronger attraction to electrons.
Electronegativity/Ionization Energy
Look at the positions of Fluorine and Francium on the periodic table.
Francium doesn’t need another electron to become stable. It actually would be more stable by giving one away. (Has lowest ionization energy due to 6 full shells of shielding.)
Electronegativity/Ionization Energy
Fluorine needs one more electron to fill its valence shell. It has the strongest electronegativity. The closer the valence electrons are to the nucleus, the stronger the electronegativity. (The valence e- are closer to the positive nucleus.)
Ionization energy & Electronegativity
H He
Li Be B C N O F Ne
Na Mg
Al Si P S Cl Ar
K Ca
Fe Cu
Zn
Br
Ag
Sn I
Au
Hg Pb
U
Place our 32 elements into correct places
Fr
H He
Li Be
B C N O F Ne
Na Mg Al Si P S Cl Ar
K Ca
Fe Cu
Zn
Br
Ag
Sn I
Au
Hg Pb
U
Alkali Metals 1 IA
2 IIA
Alkaline Earth Metals
3 4 75 86 9 10
11
12
Transition Metals
13 IIIA
Boron
Group
14 IVA
15 VA
16 VIACarbon Group
Nitrogen Group
Oxygen Group
17 VIIA
18 VIIIA
Halogens
Noble Gases
Lanthanides
Actinides
Fr
1
2
3
4
5
6
7
1
2
3
4
5
6
7