periodic law review chapter 5. this man organized the periodic table by increasing atomic mass. this...
TRANSCRIPT
• This man organized the periodic table by increasing atomic mass.
• This man organized the periodic table by increasing atomic number.
• The definition of periodic law is…
Dmitri Mendeleev
Henry Moseley
Physical and chemical properties are periodic functions of their atomic numbers.
• Periodic functions means….
• The name of the first family.
• The name of the second family.
A repeating trend because of..
Alkali metals
Alkaline Earth Metals
• The name of the 2nd to last family.
• The name of the last family.
• This family all ends in s2
Halogens
Noble Gases
Alkaline Earth Metals
• This family ends in p6
• This family ends in s1
• This family ends in p5
Noble Gases
Alkali Metals
Halogens
• These three families are highly reactive.
• This family is relatively unreactive.
• This family gains 1e- when bonding.
Alkali metals, halogens, and alkaline earth metals
Noble gases
halogens
• This family loses 1 e- when bonding.
• This family loses 2e- when bonding.
• This family has a full s and p orbital in the principal energy level.
Alkali metals
Alkaline earth metals
Noble gases
• The definition of electronegativity…
• The trend across a period….
• The trend down a family/group.
The measure of the tendency of an atom to gain an electron from another atom.
Electronegativity increases.
Electronegativity decrease or remain the same.
• The definition of electron affinity…
• The trend across a period….
• The trend down a family/group.
The energy change that occurs when an electron is acquired by a neutral atom.
Electron affinity become more negative in the p block; becomes more positive going from group 1 to group 2.
The energies become less.
• The definition of ionization energy…
• The trend across a period….
• The trend down a family/group.
The energy required to remove one electron from a neutral atom of an element.
Ionization energies of the main group elements increase across a period.
Ionization energies of the main group generally decrease down a group.
• The definition of atomic radius…
• The trend across a period….
• The trend down a family/group.
The average distance between two bonded atoms.
Atomic radius decreases across a group.
Atomic radius increases down a group.
• The definition of ionic radii…
• The trend across a period….
• The trend down a family/group.
The average distance between 2 bonded atoms that are a cation or anion.
Cationic radii decrease across a period. Anionic radii decrease across each period.
Ionic radii (cationic and anionic) increase down a group.
• The definition of valence electrons…
• The trend across a period….
• The trend down a family/group.
The number of electrons found in the outermost s and p orbitals. They are available to gain, lose or share.
Valence electrons increase by 1 in the main group.
Valence electrons remain the same in each family.
• How many atoms are in 1 mol?
• What is the above number referred to as?
• The number of protons is called?
6.022 x 1023
Avogadro’s number
Atomic number
• The number of protons + neutrons is called?
• Atoms of the same element which differ in the number of neutrons are called?
• The average mass taking into account the abundance of all of the isotopes of that element is called?
Mass number
isotopes
Atomic mass (that’s why it is a decimal on the periodic table.
• How do you obtain the mass number when all you are given on the periodic table is atomic number and atomic mass?
• The element [He] 2s2
• The element [Kr] 5s1
Rounding the atomic mass to the nearest whole number will give you the mass number of the most common isotope.
Be
Rb
• The electron configuration for K.
• The electron configuration for C.
• The electron configuration for Kr.
1s22s22p63s23p64s1
1s22s22p2
1s22s22p63s23p64s23d104p6
• The noble gas configuration for P.
• The noble gas configuration for As.
• The noble gas configuration for Ne.
[Ne]3s23p3
[Ar]4s23d104p3
[He]2s22p6
• Convert 4 .0mol O to atoms of O.
• Convert 25.0 x 1023 atoms S to mol S.
• Convert 14.0 g Mg to mol Mg.
4.0 mol O x 6.022 x 1023 atoms =2.4 x 1024
1 mol O
25.0 x 10 23 atoms S x 1 mol =4.15 mol S
6.022 x 1023 atoms
14.0 g Mg x 1 mol Mg = .576 mol Mg
24.30 g Mg