the periodic table. dmitri mendeleev (1834 – 1907) he organized elements into the first periodic...

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The Periodic Table

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Page 1: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The Periodic Table

Page 2: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Dmitri Mendeleev(1834 – 1907)

•He organized elements into the first periodic table

•He arranged elements by increasing atomic mass

Page 3: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Henry Moseley(1913)

•He arranged elements according to atomic number rather than atomic mass

•The modern periodic table is arranged by atomic number

Page 4: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Periodic Law

The periodic law states that

there is periodic repetition of chemical and physical properties of elements

Page 5: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The Modern Periodic Table

There are 18 groups (columns up and down)

The group A’s (the tall columns) are called representative elements

Page 6: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

•The group B’s (the middle columns) are called transition metals

Page 7: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

There are seven periods(rows across the periodictable)

Page 8: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Metals are to the LEFT of the zig-zag line (except hydrogen!)

Metals in yellow

Page 9: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Nonmetals are to the RIGHT of the zig-zag line

nonmetals in red

Page 10: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Metalloids

•Metalloids are those elements ON the zig-zag line

Metalloids border the zig-zag line

Page 11: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Now . . .YOU fill in the chart using your book!

Page 12: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Metals

•solid at room temperature

•shiny (have luster) and smooth

•good conductors of heat and electricity

Page 13: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Metals

•malleable – “bendable” (can be pounded into sheets)

•ductile - can be pulled into wires

Page 14: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Metals

•react with acids

•mercury (Hg) is the only LIQUID metal

Page 15: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Nonmetals

•generally gases or brittle, dull looking solids at room temperature

•poor conductors of heat and electricity

•Bromine (Br) is the only LIQUID nonmetal

Page 16: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Metalloids

•sometimes called semimetals

•metalloids have properties of both metals and nonmetals

Page 17: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Metalloids

•silicon and germanium are two of the most important metalloids (they’re used in computer chips and solar cells)

Page 18: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Trends of the Periodic Table

Page 19: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Periodic LawIf elements are organized according to atomic number, their properties will repeat periodically

Page 20: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Four Periodic Trends:

1.Atomic radii

2.Ionic radii

3.Electronegativity

4.Ionization energy

Page 21: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Atomic RadiusThe atomic radius basically tells you the size of the atom. It is half the distance between two nuclei of identical atoms bonded together.

radius

Page 22: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The trend: atomic radii DECREASE across a

period•Why?

•Each time a positive proton is added to the nucleus, the negative electrons feel a greater attraction to the positively-charged nucleus and get “pulled in” tighter

Page 23: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Decreasing – getting smaller!

Page 24: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Trend: atomic radiiINCREASE down a group

•Why?

•electrons are added to higher and higher energy levels as you go down

Page 25: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Atomic radii DECREASE down a group!

Page 26: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The farther the electrons from the nucleus, the larger

the atomic radii!!!!!

Page 27: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Try these . . .

1.Which element has the larger atomic radius: C or F?

carbon

2.Which element has the smaller atomic radius: Ar or Kr?

argon

Page 28: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Ionic Radii

•Is basically the size of an ion or half the distance between the nuclei of two ions bonded together

What is ion???

Page 29: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Ionic Radii

•Ion – an atom with a charge (+ or - )

•An ion is formed when atoms lose or gain electrons

Page 30: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

•What happens to an atom if it LOSES an electron?

it loses a negative charge so it becomes POSITIVE

Na +1

Page 31: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

•A positively charged ion is called a cation

Na +1

Page 32: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Positive ions (cations) are smaller than the atoms they come from because they lose electrons making the atom smaller.

Na Na +1

Page 33: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

•What happens to an atom if it GAINS an electron? It gets more negative

(so it has a negative charge) Cl -1

Page 34: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

A negatively charged ion is

called an anion.

Cl -1

Page 35: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Negative ions (anions) are LARGER than the atoms they come from because they gain electrons – making the atom LARGER!

Cl -1 Cl

Page 36: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The trend:

•See the board

Page 37: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Remember . . .

•all atoms want a full octet (8 valence electrons)

•atoms with 1 valence electron will give up that electron VERY QUICKLY to become stable

Page 38: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

example: •sodium has one valence electron: 1s22s22p63s1 •if sodium gives it away, then the configuration will be:

1s22s22p6

•sodium will have a full octet

Page 39: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

•atoms with 7 valence electrons will hold on to those electrons VERY TIGHTLY

•they try to get one more and become stable

Page 40: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Ionization Energy•The amount of energy needed to remove an electron

•think of it as: how tightly an atom holds on to its electrons

Page 41: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The trend:•ionization energy INCREASES across a period

Page 42: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

•Why?

•the more valence electrons an element has, the more difficult it is to remove them!

Page 43: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The trend:•Ionization energy DECREASES down a group

Page 44: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

•Valence electrons in higher energy levels are NOT held as tightly because they are farther from the nucleus

•Therefore, it is easier to remove an electron that is farther from the nucleus

Page 45: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Try these . . .

•Which has a higher ionization energy: Na or Cl

Chlorine •Which has a lower ionization energy: Li or O

Lithium

Page 46: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Electronegativity

•The ability of an atom to attract electrons to itself

Page 47: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The Trend: electronegativity

INCREASES across a period •Why?•atoms are trying harder to attract electrons to get a full octet

Page 48: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

The trend: electronegativity

DECREASES down a group

•Why?

•it is harder to hold on to the electrons that are farther away from the nucleus

Page 49: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass
Page 50: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Try these . . .

•Which element is more electronegative? F or Br

Fluorine•Which element is more electronegative? B or Ca

Boron

Page 51: The Periodic Table. Dmitri Mendeleev (1834 – 1907) He organized elements into the first periodic table He arranged elements by increasing atomic mass

Finished!