Chapter 12 - Chemical
PeriodicityChapter 12: Chemical periodicity
The Periodic Table and its development
The modern Periodic Table
Electrion configurations and periodicity [Practice
]
Patterns in atomic size [Practice
]
Patterns in ion-formation energy [Practice
]
Patterns in electron-attraction (electron affinity) [Practice
]
Patterns in ionic size [Practice
]
Patterns in electronegativity [Practice
] [Reference]
The noble gasses
The alkali metals and alkaline earth metals
The aluminum group
The carbon group
The nitrogen group
The oxygen group
The halogens and hydrogen
The transition metals and inner transition metals
Chapter 12 Note: See Chempire's Online Periodic Table 12-1 The Development of the Periodic Table
- Mendeleev took first steps in organizing the elements according to atomic mass and periodicity in their properties. - Moseley arranged them in order of atomic number.
12-2 The Modern Periodic Table- Rows = periods; columns = groups.
- Groups numbered and lettered. 1A-7A (only A) are representative elements. - Periodic Law: when the elements are arranges in order of increasing atomic number, there is a periodic
pattern in their physical and chemical properties.
12-3 Electron Configurations and Periodicity [Practice
]- The noble gasses: outer s and p energy levels are filled.
- The representative elements: outer s and p energy levels are partially filled. - The transition metals: outer s and nearby d contain electrons.
- The inner transition metals: s and nearby f contain electrons.
12-4 Periodic Trends in Atomic Size [Practice]- Covalent atomic radius (atomic radius): "half the distance between the nuclei of two atoms in a
homonuclear diatomic molecule" or, more simply, the radius of the atom, from the nucleus out. - Atomic size increases as you go down, decreases as you go right.
12-5 Periodic Trends in Ionization Energy [Practice]
- Ionization energy: how much energy is needed to remove one electron from a gaseous atom. - See Chempire's Online Ionization Energies chart.
- Ionization energies decrease as you go down, increases as you go right.
12-6 Periodic Trends in Electron Affinity [Practice]- Electron affinity: energy released when an electron is added.
- Electron affinity increase as you go to the right, decreases as you go down.
12-7 Periodic Trends in Ionic Size [Practice]- Ionic radii start large at group 5, get smaller until group 7, wraps around to the next period, and
continues to get smaller until the next group 5 element. Ionic radii get larger as you move down a period. 12-8 Periodic Trends in Electronegativity [Practice] [Reference
]- Electronegativity is an atom's ability to attract an electron.
- They get larger as you go to the right, and smaller as you go down. 12-9 Noble Gasses- Noble gasses rarely react.
12-10 The Alkali Metals and the Alkaline Earth Metals- Group 1A is the Alkali Metals. They react violently with water.
- Group 2A is the Alkaline Earth Metals. Less reactive than 1A. 12-11 The Aluminum Group- Mostly metals. Aluminum used frequently, others rare.
12-12 The Carbon Group- Carbon: diamond and graphite are two of its forms. - Silicon is the second most abundant element on earth. It is a semiconductor.
12-13 The Nitrogen Group
- N is essential to life. It and P are found in DNA. 12-14 The Oxygen Group
- Oxygen is the most abundant element on earth. 12-15 The Halogens and Hydrogen- Halogens have many uses. - Hydrogen is a group in itself.
12-16 The Transition Metals and the Inner Transition Metals- They are typical metals. Tungsten is used in lightbulbs, mercury in thermometers. Go to Chapter:
1 2
3 4 5
6 7 8
9 10 11
12 13 14
15 16 17
18 19 20
|
