All elements are composed of tiny indivisible particals called Atoms.
Dalton 2nd Theory
Atoms of the same elements are identical.
Dalton 3rd Theory
Atoms of different elements can physically mix together or can chemically combine with one another in simple whole-number ratios to form compounds.
Dalton 4th Theory
Chemical reactions occur when atoms are separated, joined, or rearranged.
Thompson
-Cathrode Ray Tube.
-Charge to mass ratio of the electron.
Rutherford
-Gold Foil Experiment.
-Positive charge localized in the atom.
Millikan
-Oil drop experiment.
-Mass of the electron or the electron charge.
Mendeleev
First periodic table. Arranging by Increasing Atomic Mass.
Mosely
Perfected the periodic table. Arranging by Increasing Atomic Number.
Isotopic Notation
Mass number 33
P2- Charge
Atomic #
15
-Neutrons= Mass - Atomic #
-Protons=Atomic#
Metals
-High electricity and heat conductivity.
-Metals are ductile and malleable.
-Lose electrons in reactions.
-Shiny(lustrous).
-High melting point.
-Corrosion, React Vigoriously with acids not bases, lose valence electrons to form ions when bonding, like to react with nonmentals.
Non-Metals
-Poor conductors of heat and electricity.
-Solid nonmetals are brittle.
-Little or no metallic luster(dull).
-Most are gases at room temperature.
-Low density.
-Low melting point.
-Not malleable or ductile.
-Likes to react with metals,Gain Valence electrons to ions when bonding.
Metalloids
-Siny or dull
-Conductivity of heat and electricity better than nonmetals but not as good as metals.
-Solid at room temperature.
-Ductile and Malleable
-Elements gain or lose electrons when bonding.
Halogens
Group 7A
Noble Gases
Group 8A
Transition Metals
Groups in the middle(3-12)
Inner transition metals(Rare earth metals)
The last two bottom rows
Alkali Metals
Group 1A-EXECPT Hydrogen
Alkaline Earth Metals
Group 2A
Average atomic mass
(NA)(AMU)+(NA)(AMU)+(NA)(AMU) =AMU
100
Natural ambundance=NA
Atomic Mass Unit=AMU
Natural Ambundance times Atomic Mass Unit divided by 100 equals the AMU
Atomic Radius
Trend- Increasing down/Inceaising left
Ionization Energy
Trend-Increasing up/Increasing right
-Decreses down a group because the valence electrons are farther from the nucleus and are held less tightly. Increases right because the atomic size decreses and valence electrons held more tightly.
-Noble gases are stable and they don't react/ they don't want to form bonds/ not wnating to gain or lose and electron.
1stionization energy is the energy required to remove the first electron.
2ndionization energy is the energy required to remove the second electron.
3rdionization energy is the energy required to remove the third electron.
-You can tell what level of energy when looking on a table is the sudden spikes in number.
Ionic Size
-Anions are bigger than the atom from which they were formed because they gain and electron and increasing in size.
-Cations are smaller then the atoms from which they were formed because they lose and elcetron becoming smaller in size.
Electronegativity
-The tendancy of an atom to attract electrons to itself.
-FONCL(phone call)-trend stops here
-Noble gases have no elctronegativity do not want to gain electrons to form ions.
-Elements with high electronegativty(nonmetals) tend to gain electron to form anions.
-Elements with low electronegativty(metals)often lose electrons to form cations.
Electron dot configuration
-You can tell how many valence electrons by the group number.(the number with letter)EXECPT HELIUM.Each letter hold 2 electrons.
-Convention(silicon/carbon)
Valence electron in electron configuration
_Match the number infront.Then count the expoents. then add it up.
Aufbau Chart
S=2
D=10
P=6
F=14
Simplified version of electron configuration
When it is a noble gas then go back to the other noble gas. Kr=[Ar]4s23d104p6
But when a reqgular element then just go back to the noble gas then start from there.