The History of your Periodic Table Ch. 6 · Dobereiner--Grouped elements with similar properties in...
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The History of your Periodic Table Ch. 6.1
Transcript of The History of your Periodic Table Ch. 6 · Dobereiner--Grouped elements with similar properties in...
The History of your Periodic Table Ch. 6.1
The History of your Periodic Table Ch. 6.1
Dobereiner--Grouped elements with
similar properties in groups of three called triads.
-studied their atomic masses.
The History of your Periodic Table Ch. 6.1
Dobereiner--Grouped elements with
similar properties in groups of three called triads.
-studied their atomic masses.
The History of your Periodic Table
John Newlands--grouped elements in order of atomic
mass-Called it the Law of Octaves- 7 columns eighth element goes in
the first column- Elements in same column had the
similar properties
The History of your Periodic Table
Dmitri Mendeleev- (father of the periodic table)-Grouped elements in order of atomic mass-Elements with similar properties were placed in
same column-HIS MOST IMPORTANT CONTRIBUTION1. He left spaces open for undiscovered elements
(big jumps in mass)2. Predicted properties in those spaces with
amazing accuracy
The History of your Periodic Table
Henry Mosely--Grouped elements in order of atomic
number-credited with modern periodic tableCame up with Period Law-
-physical and chemical properties of elements are a periodic function of their atomic numbers
Periodic Table
Periods-a horizontal row of elements.-Tells you the electron energy levels.
Periodic TableGroups (families)
-a vertical column of elements.-Tells us the # of valence electrons
and the elements’ chemical properties. (A Group)
-Transition metals make B Group
Inner Transition Metal Placement
Ch. 6.2 Periodic Table
3 types of elements1. metals
on the left side and the center, form cations
2. nonmetalson right, form anions
3. metalloidsborder control
Ch. 10.1 Periodic Trends
A pattern of characteristics that occur over and over again
Ex days of the weeksThere are many trends on the Periodic Table
1. Metallic Trends
Going left to right elements become less metallicGoing Down elements become more metallic
2.
Atomic Radii
Atomic Radii is measured by taking the distance from the nucleus to the outer energy level
Can you tell me the trend?
Atomic Radius
DecreasesIn
crea
ses
But Why?
Atomic RadiiAs you go down a group you are adding an energy level, or another layer of electrons
3.
Ionic Radii
Ions aren't the same size as the atoms they come from.Cations are smaller than the parent atomAnions are bigger than the parent atom
Ionic Radii –
Why Cations Smaller?
By losing electrons, they also lose a whole energy level, therefore, becoming smaller in size
Ionic Radii –
Why anions bigger?
When they gain electrons, the outermost becomes full. So less force is felt by the nucleus, the atom spreads out. (becoming stable)
4. Ch. 10.2 Ionization Energy
The energy required to removethe most loosely held electron in the outer energy level of an atom.The less energy required, the more reactive the metal
Ionization Energy
Increases
Dec
reas
es
Atomic Radii
+
+
e-
e-
Needs more energy to be lost
Needs less energy to be lost
Shielding Effect
5. Reactivity for Metals
Reactivity increases because the atom is more willing to give away its electron and react. (Ionization energy decreased)
6. Electronegativity/Electron Affinity
Measure of an atoms attraction for an electron.Nonmetals have high attraction for electronsThe higher the attraction the more reactive the nonmetal
Electronegativity/Electron Affinity
Increases
Dec
reas
es
Electronegativity
Electronegativity/Electron Affinity
One exception- noble gasesWhy?They don’t want electrons, they are happy and full already
7. Reactivity for nonmetals
Going UP a group for nonmetals increases their reactivityThe reason more electron affinityFluorine is the most reactive nonmetal.
Ch. 11
Families of the Periodic Table
Periodic Table -
Regions
Transition Metals
Alkaline Earth Metals
Alkali Metals
Metalloids
Other Metals
Non MetalsHalogens
Nobel Gases
Inner Transition Metals
Ch. 11.1 Alkali Metals Group 1
Most reactive metals (one valence e-)Found as compounds (salts).Soft metalsGood conductors.
Brainiac Video
Cesium
Alkaline-earth Metals Group 2
Similar to Alkali but less reactive because they have 2 valence electronsMostly found as compounds
Calcium
Ch. 11.3 Transition Metals Group 3-12
Less reactive than groups 1 and 2Strong metals (Fe, Cr, Ti, Co, Zn)Good conductors
Transition Metals
All solids with the exception of mercuryValuable metals (Ag, Au, Pt, Cu, Ni)
Ch. 11.3 Inner Transition Metals
Two rows at the bottomRare earth metals93 and above are manmade
Uranium
Metalloids (Semiconductors)
7 elements on the stepProperties of both metals and non-metals.Silicon the most familiar (computer chips)Arsenic is rat poison
Silicon
Arsenic Exposure
Non MetalsAre not able to conduct electricity or heat very well.Found in groups 13-18 with the exception of hydrogen.
HYDROGEN
It is not a alkali metalIt is a gas/nonmetalA very explosive gas.It is located in group one because it has one valence electronHindenburg
Carbon
Found as an element (coal, diamond, graphite)Found in millions of different compoundsCalled Organic Compounds
Oxygen and Nitrogen
Oxygen is the most common element found on EarthNitrogen most common gas found in the atmosphere
Ch. 11.2 Halogens Group 17
Highly reactiveForm salts with group 1Used to kill bacteria (Cl, F, I)Bromine the only liquid nonmetal
Noble Gases Group 18
Stable and inert gasesDon’t form compounds.Full valence shell.Fun with He
Xenon Bulbs
Neon
Krypton a stable violet colored gas?
