Post on 03-Jan-2016
Periodic Table Review
1. Parts of the Periodic Table
2. Introduction to the Periodic Table
3. Atomic Structure and the Periodic Table
4. Periodic Trends in Atomic Radius, Ionization Energy, and Electronegativity
5. Isotopes and Average Atomic Mass
The columns are called groups or families. Groups have similar physical and chemical properties and the same number of valence electrons.
Name the groups boxed in yellow, orange, green and blue.
Name the groups boxed in yellow, orange, green and blue. Alkali metals, Alkaline Earth metals, Halogens, and Noble Gases
The rows are called periods. The period number matches the principle energy level of the element. This will be the principle energy level of the valence electrons.
What is the principle energy level of Nickel, Ni?
What is the principle energy level of Nickel, Ni? 4—it is in the row numbered 4
Using the Periodic Table
Let’s use the periodic table to answer some questions about Silicon
How many protons does Silicon have?
How many protons does Silicon have? 14 protons = atomic number
How many electrons does neutral Silicon have?
How many protons does Silicon have? 14 protons = atomic number.
How many electrons does neutral Silicon have? 14 electrons (# electrons = # protons in neutral atoms)
How many neutrons does Silicon-30 have?
How many protons does Silicon have? 14 protons = atomic number.
How many electrons does neutral Silicon have? 14 electrons (# electrons = # protons in neutral atoms)
How many neutrons does Silicon-30 have? 16 neutrons. Silicon-30 is an isotope of Silicon. It has a mass number of 30. The mass number is protons + neutrons.
How many protons does Silicon have? 14 protons = atomic number.
How many electrons does neutral Silicon have? 14 electrons (# electrons = # protons in neutral atoms)
How many neutrons does Silicon-30 have? 16 neutrons. Silicon-30 is an isotope of Silicon. It has a mass number of 30. The mass number is protons + neutrons.
What is the atomic mass of Silicon?
How many protons does Silicon have? 14 protons = atomic number.
How many electrons does neutral Silicon have? 14 electrons (# electrons = # protons in neutral atoms)
How many neutrons does Silicon-30 have? 30 neutrons. Silicon-30 is an isotope of Silicon. It has a mass number of 30. The mass number is protons + neutrons.
What is the molar mass of Silicon? 28.0855 amu (this is the same as the atomic mass on the periodic table)
How many protons does Silicon have? 14 protons = atomic number.
How many electrons does neutral Silicon have? 14 electrons (# electrons = # protons in neutral atoms)
How many neutrons does Silicon-30 have? 30 neutrons. Silicon-30 is an isotope of Silicon. It has a mass number of 30. The mass number is protons + neutrons.
What is the molar mass of Silicon? 28.0855 grams/mole (this is the same as the atomic mass on the periodic table)
How many valence electrons does Silicon have?
How many protons does Silicon have? 14 protons = atomic number.
How many electrons does neutral Silicon have? 14 electrons (# electrons = # protons in neutral atoms)
How many neutrons does Silicon-30 have? 30 neutrons. Silicon-30 is an isotope of Silicon. It has a mass number of 30. The mass number is protons + neutrons.
What is the molar mass of Silicon? 28.0855 grams/mole (this is the same as the atomic mass on the periodic table)
How many valence electrons does Silicon have? 4 valence electrons. Look for electrons in the highest principle energy level.
An s orbital holds 2 electrons w/ opposite spins
Each p orbital holds 2e- with opposite spins
Each d orbital holds 2e- with opposite spins
The s suborbitals fills
The orbitals and the periodic table
The p suborbitals fill
The orbitals and the periodic table
The d suborbitals fill
The orbitals and the periodic table
Valence electron configuration and the periodic table
All group 3a elements have the valance electron configuration ns2np1 and 3 valence electrons
Valence electron configuration and the periodic table
All group 5a elements have the valance electron configuration ns2np3 and 5 valance electrons.
Valence electron configuration and the periodic table
What is the valence configuration of the halogens?
Chemistry SOL Review—Atomic Structure
Valence electron configuration and the periodic table
What is the valence configuration of the halogens? ns2np5.
Periodic Trends in Atomic Radius, Ionization Energy, and Electronegativity.
Atomic Radius: Half the distance between two atoms nuclei when they are bonded.
Ionization Energy: The energy needed to remove an electron from an atom.
Electronegativity: The tendency of an atom to attract electrons to itself when chemically combined with another element.
Atomic Radius: Half the distance between two atoms nuclei when they are bonded.
1 2 13 14 15 16 17 18
First Ionization Energy: The energy needed to remove an electron from an atom.
Ionization energy increases as you move to higher number groups. Group 8a has the highest ionization energy.
Ionization energy decreases as you move down the periodic table.
First Ionization Energy: The energy needed to remove an electron from an atom.
Electronegativity: The tendency of an atom to attract electrons to itself when chemically combined with another element.
The halogen group has the highest electronegativity of the families. The first period has the highest electronegativity. Noble gases do not have electronegativity as the valence shell is already full.
Anions, Cations, and Electron Configuration
Cations form by losing valance electrons to achieve a stable outer energy level.
Chemistry SOL Review—Atomic Structure
Anions, Cations, and Electron Configuration
Cations form by losing valance electrons to achieve a stable outer energy level.
So Li loses the 2s1 electron to form Li+1.
Mg loses both 3s2 electrons to form Mg+2
Al loses three electrons from 3s23p1 to form Al+3
Chemistry Review—Atomic Structure
Anions, Cations, and Electron Configuration
Anions form by gaining valance electrons to achieve a stable outer energy level.
So F becomes F1- by gaining a 2p electron to have the new valance configuration 2s22p6. S becomes S2- by gaining two 2p electrons to have the new valance configuration 3s23p6. N becomes N3- by gaining three 2p electrons to have the new valance configuration 2s22p6.
126C 13
6C 14
6C
Isotopes: elements with the same number of protons, but a different number of neutrons.
Carbon-14 has ___ protons and ___ neutrons
126C 13
6C 14
6C
Isotopes: elements with the same number of protons, but a different number of neutrons.
Carbon-14 has 6 protons and 8 neutrons
126C 13
6C 14
6C
Isotopes: elements with the same number of protons, but a different number of neutrons.
You figure out the average atomic mass of a compound by using a weighted average of the mass number for each isotope.
Example: a sample contains 10% C-13, 60% C-12 and 40% C-14. The average atomic mass is
(0.10 x 13) + (0.60 x 12) + (0.30 x 14) = 12.7