Download Learning Guide 3

Learning objectives:
After completing this unit of study, you should be able to:
• An element’s location on the periodic table gives an indication of its physical and chemical
properties.
• Elements on the Periodic Table are arranged in order of increasing atomic number.
• Elements are classified as metals, nonmetals and metalloids based on their properties and
location on the periodic table.
• Groups 1, 2, and 13-18 have the same number of valence electrons in the group, and
therefore have similar chemical properties. Helium is the exception to this.
• Each group shows trends in atomic radius, ionic radius, Electronegativity, first ionization
energy, and metallic and nonmetallic properties.
• Each period shows trends in atomic radius, Electronegativity, first ionization energy, and
metallic and nonmetallic properties.
• When an element becomes an anion by gaining electrons, the radius increases.
• When an element becomes a cation by losing electrons, the radius decreases.
• Some elements exist as two or more forms in the same phase due to differences in molecular
or crystal structures, and therefore have different chemical and physical properties. These are
called Allotropes. Carbon has the allotropes coal, graphite, diamond, and fullerenes. Oxygen
has the allotropes O2 & O3.
Learning Guide 1: P.T. Basics
1. Dimitri Mendeleev organized the 1st periodic
table by atomic mass.
2. Mosley re-organized the periodic table by
atomic number.
3. This was better because there are places on the
periodic table that mass goes down, but atomic
number ALWAYS INCREASES BY 1.
4. Modern Periodic Law states that elements are
organized by atomic number, and properties are
determined by number of valence electrons.
Learning Guide 1: P.T. Basics
Atomic Mass
Oxidation States (charge)
Symbol
Atomic Number
Electron Configuration
Learning Guide 1: P.T. Basics
6. A PERIOD is a horizontal row on the periodic
table.
7. All elements in a period have valence
electrons in the same ring.
8. The number of valence electrons go up by one
as you go cross a period.
Metals, Metalloids & Nonmetals:
Learning Guide 1: P.T. Basics
9. Metals are located to the left and below the
staircase line.
10. Nonmetals are located to the right and
above the staircase line.
11. Metalloids (Semimetals) are located
bordering the staircase line.
States of Matter at RT
Learning Guide 1: P.T. Basics
12. The majority of the elements are SOLID at
room temperature.
13. There are 2 elements that are liquids at room
temperature: Bromine (Br) & Mercury (Hg).
14. The gases at room temperature are :
Hydrogen (H), Helium (He), Neon (Ne), Argon (Ar),
Krypton (Kr), Xenon (Xe), Radon (Rn), Flourine (F),
Oxygen (O), Nitrogen (N), Chlorine (Cl)
Learning Guide 1: P.T. Basics
15. A GROUP is a vertical column on the periodic
table.
16. Another name for a group is a family.
17. All elements of a group have the same
number of valence electrons.
18. All members of a group have similar
reactivity.
Learning Guide 1: P.T. Basics
Symbol
Name
Atomic #
Period
Group
Pb
Potassium
45
Iron
3
17
Complete chemdo 1
Metals, Metalloids & Nonmetals:
METAL
NONMETAL
Located to the left & below the
staircase line
Located to the right above the
staircase line
•
•
•
•
•
•
•
•
•
•
•
•
•
•
Solid ( except Hg(l) )
Luster (shiny)
Malleable ( flattens)
Ductile (wire)
Conducts electricity
Conducts heat
Hi density
Soft
Solid, liquid or gas
Dull
Brittle
Hard
Don’t conduct electricity
Don’t conduct heat
Loses electrons
Gains electrons
Form cations ( + ion)
Form anion (- ion)
Ions smaller than atom
Ions bigger than atom
Good conductor of heat & electricity
Poor conductor of heat & electricity
Lo Ionization Energy
Hi Ionization Energy
Lo Electronegativity
Hi Electronegativity
Most active metal lower left
Most active nonmetal upper right
Learning Guide 2: M/NM/SM
1. Nonmetal ions are larger than the atoms
from which they are formed from because
they gain electrons.
2. Metal ions are smaller than the atoms from
which they from because they lose electons.
Learning Guide 2: M/NM/SM
3. Transition metals are located in groups 3-12.
4,,The transition metals have multiple (more than
one) oxidation states.
4. 2 unique characteristics are multiple oxidation
states and colored solutions in water.
Learning Guide 2: M/NM/SM
5. Metalloids are elements that have properties
of both metals and nonmetals.
6. Metalloids border the staircase line.
Learning Guide 2: M/NM/SM
7. Noble gases are found in group 18.
8. They are unique because they do
not react with other elements (they
are snobs).
Learning Guide 2: M/NM/SM
9. Allotope: elements that exist as two or more
forms in the same phase due to differences in
molecular or crystal structures, and therefore
have different chemical and physical
properties.
10. a. Carbon (C) has the allotropes coal,
graphite, diamond, and fullerenes.
b. Oxygen has the allotropes O2 & O3.
Phosphorus has 3 allotropes
Allotropes of Carbon:
Metals, Metalloids & Nonmetals:
Metals, Metalloids & Nonmetals:
Property
METAL
to left and below staircase line
2/3 of elements
SEMIMETAL
border staircase line
NONMETAL
To right & above staircase line
1/3 of elements
LOCATION
yes
maybe
no, dull
yes
Maybe
no
yes
Maybe
No, hard & brittle
solid
solid, liquid & gas
LUSTER – SHINY?
CONDUCTIVE OF
HEAT & ELECTRICITY?
MALLEABLE – CAN BEND
WITHOUT BREAKING?
solid, except Hg(l)
PHYSICAL STATE AT RT?
Cu, Au, Ag, Pt
B, Ge, Si, Sb, Te, At
F, C, N, O, Cl…
IMPORTANT EXAMPLES:
# OF
VALENCE ELECTRONS
TENDENCY TO LOSE OR TO
GAIN ELECTRONS?
GENERAL ATOMIC
STRUCTURE
ARE IE & EN HIGH OR LOW?
1, 2, 3,
tend to lose e- forming cations,
getting smalller
less than 4 valence electrons
Low
3, 4,,5
Can gain or lose
Around 4 valence electrons
Medium
5, 6, ,7
tend to gain e- , forming
anions, getting larger
more than 4 valence electrons
High
Metal & Nonmetal LAB
METALS
• Luster: shiny
• Mostly solid
• Soft:
Malleable – can flatten easily
Ductile – can be a wire
• Conducts heat & electricity
(Cu wire , Ag & Au jewelry)
• Reactive
( bubbles w/ HCl, darkens w/
CuCl2)
NONMETALS
• Dull (not shiny)
• Can be solid or liquid or gas
• Hard & Brittle
( crushes to a powder easily)
• Does NOT conduct
• Does NOT react
Which elements that you tested were
METALS?
LIST:
Support:
Which elements that you tested were
NONMETALS?
LIST:
Support:
Which elements that you tested were
METALLOIDS?
LIST:
Support:
Complete chemdo 2
Groups/Families of the Periodic Table
Nuclear Charge
• The charge of the nucleus
• The number of protons = atomic number
• Greater nuclear charge means greater attraction
of nucleus on the electrons
• Means smaller radius, harder to lose e- (IE)
easier to gain e- (e-neg)
Shielding
• Kernel electrons interfere with the nuclear
attraction for valence electrons.
• More energy levels mean that it is easier to
remove an e- and harder to gain an e-, because
protons are shielded by the kernel e- in
between them.
Ionization Energy
• The amount of energy needed to remove the
outermost electron.
• More IE = harder to remove an electron
• Less IE = easier to remove an electron
Learning Guide 3:
Trends in Groups & Families
nuclear
charge
4. As you go left to right across a period, nuclear
charge increases, electrons are stronger
attracted and more energy is required to
remove them
Learning Guide 3:
Trends in Groups & Families
nuclear
charge
• 5. As you go top to
bottom down a group,
valence elevtrons are
farther from the
nuclesu and it is easier
energy is required to
remove them
Atomic Radius
DEF: ½ the distance between 2 atoms OR THE RADIUS OF AN ATOM
Learning Guide 3:
Trends in Groups & Families
7. As you go left to right across a period atomic
radius decreases.
8. As nuclear charge increases as you go left to
right across a period, the number of protons
increase, pulling tighter on electrons and making
the radius smaller.
Learning Guide 3:
Trends in Groups & Families
9. Shielding effect across a period is constant
because balance electrons are in the same energy
level in the same period.
Li
Be B
C
N
O
F
Ne
e- config: 2-1
2-2 2-3 2-4 2-5 2-6 2-7 2-8
Across a period sheilding has NO EFFECT!!
Learning Guide 3:
Trends in Groups & Families
10. As you go top to bottom down a group atomic
radius increases.
11. The number of occupied energy levels
increases as you go top to bottom down a group.
12. Shielding causes atomic size to INCREASE as
atomic number increases down a group.
Learning Guide 3:
Trends in Groups & Families
13. ION: a charged part of an atom, resulting from
the loss or gain of an electron.
14. Ionic Radius:
LOSS of electron  ion is SMALLER than atom
GAIN of electron  ion is BIGGER than atom
Learning Guide 3:
Trends in Groups & Families
15. Metals tend to lose electrons to form an ion
with a radius that is smaller than the atom.
16. Nonmetals tend to gain electrons to form an ion
with a radius that is larger than the atom.
Learning Guide 3:
Trends in Groups & Families
17. Electronegativity: A measure of how easily an atom
gain gain (attract) electrons. Bigger EN number: easier
to gain
LOOK ON REF. TABLE S!!!!!!!!
18. Flourine has highest EN value of 4.0
19. Francium has lowest EN of 0.7
Remember ionic radius???
• When an atom forms an ION that is POSITIVE,
the IONIC RADIUS is LESS THAN ATOMIC
RADIUS, because it LOSES ELECTRONS
• When an atom forms an ION that is
NEGATIVE, the IONIC RADIUS is BIGGER THAN
ATOMIC RADIUS, because it GAINS
ELECTRONS
Bohr models of 3Li, 9F, 87Fr
Pg 14-17 notepacket:
• Atomic Radius – distance from nucleus to
valence electron
• Ionization Energy: energy required to remove
the outermost electron
• Electronegativity – a measure of ability to gain
an electron
Periodicity:
• FOLLOWS A PATTERN
• There are general trends in properties as you
move left to right across a period.
• There are general trends in properties as you
move top to bottom down a group.
Periodic Trend in Number of Valence
Electrons
1 (IA)
2 (IIA)
13 (IIIA)
14(IVA)
15 (VA)
16 (VIA) 17 (VIIA) 18 (VIIIA)
Periodic Trend in Number of Valence
Electrons
1.) What is the trend in valence electron number as you go from left to right across any period on
the table?
2.) What is the trend in the valence electron number as you go down any group from top to
bottom?
3.) What is the trend in the number of energy levels as you go down any group from top to bottom?
4.) Use your answers to #2 & 3 to write a statement explaining the relationship between number of
valence electrons and the number of energy levels.
Periodic Trend in Atomic Radius
1 (IA)
2 (IIA)
13 (IIIA)
14(IVA)
15 (VA)
16 (VIA) 17 (VIIA) 18 (VIIIA)
Periodic Trend in Atomic Radius
1.)
What is the trend in atomic radii as you go from left to right across any period on the table?
2.) What is the trend in the number of protons (nuclear charge) as you go from left to right across any period on
the table?
3.) Use your answers to #1 & 2 to write a statement explaining the relationship between atomic radii and nuclear
charge (# of protons).
4.) What is the trend in atomic radii as you go down any group from top to bottom?
5.) What is the trend in the number of energy levels as you go down any group from top to bottom?
6.) Use your answers to #4 & 5 to write a statement explaining the relationship between atomic radii and the
number of energy levels.
Ionization Energy: energy required to
remove the outermost electron
1 (IA)
2 (IIA)
13 (IIIA)
14(IVA)
15 (VA)
16 (VIA) 17 (VIIA) 18 (VIIIA)
Periodic Trend in Ionization Energy
1.) What is the trend in ionization energy as you go from left to right across any period on the table?
2.) What is the trend in the number of protons (nuclear charge) as you go from left to right across any period on
the table?
3.) Use your answers to #1 & 2 to write a statement explaining the relationship between ionization energy and
nuclear charge (# of protons).
4.) What is the trend in ionization energy as you go down any group from top to bottom?
5.) What is the trend in the number of energy levels as you go down any group from top to bottom?
6.) Define shielding:
7.) Use your answers to #4 & 5 to write a statement explaining the shielding effect on onization energy .
Electronegativity – a measure of ability to
gain an electron
1 (IA)
2 (IIA)
13 (IIIA)
14(IVA)
15 (VA)
16 (VIA) 17 (VIIA) 18 (VIIIA)
Periodic Trend in Electronegativity
1 (IA)
2 (IIA)
13 (IIIA)
14(IVA)
15 (VA)
16 (VIA) 17 (VIIA) 18 (VIIIA)
Periodic Trend in Electronegativity
1.) What is the trend in electronegativity as you go from left to right across any period on the table?
2.) What is the trend in the number of protons (nuclear charge)as you go from left to right across any period on
the table?
3.) Use your answers to #1 & 2 to write a statement explaining the relationship between electronegativity and
nuclear charge (# of protons).
4.) What is the trend in electronegativity as you go down any group from top to bottom?
5.) What is the trend in the number of energy levels and shielding as you go down any group from top to bottom?
6.) Use your answers to #4 & 5 to write a statement explaining the shielding effect of number of energy levels on
electronegativity.
Periodic Trend in Melting and Boiling Points
Data Table 2: Boiling Points and Melting Points of the First 20 Elements
Atomic
Number
1
2
3
4
5
BP
(0C)
-252
-269
1327
2507
2527
Mp
(0C)
-259
-272
179
1287
2037
Atomic
Number
6
7
8
9
10
BP
(0C)
4347
-196
-183
-188
-246
Mp
(0C)
3470
-210
-219
-218
-248
Atomic
Number
11
12
13
14
15
BP
(0C)
889
1117
2327
2677
280
Mp
(0C)
97
650
659
1407
44
Atomic
Number
16
17
18
19
20
BP
(0C)
445
-34
-186
757
1487
Mp
(0C)
119
-101
-189
64
851
Graph Title: Periodic Trend in Melting Point and Boiling Point
Y-axis:
start at -300, end at 4800, each “bold” line increases
by 300. Label: TEMPERATURE (oC)
X-axis: _______ start at 0, end at 20, each “bold” line increases by 2
Label: ATOMIC NUMBER
Chem Do 3 graph
Y-axis: start at 50, increase by 10, stop at 220
X-axis : start at 10, count by .5, stop at 18
Be sure to * write a good title (1pt)
* label each axis (1 pt each)
* make a key describing the colors (1 pt)
Chem Do 3b graphs
#6: “Trend in atomic radius down group 2”
Y-axis: start at 100, increase by 10, stop at 270
X-axis : start at 0, count by 5, stop at 90
#7: “Trend in ionization energy down group 1”
Y-axis: start at 200, increase by 100, stop at
1800
X-axis : start at 0, count by 5, stop at 90
Complete chemdos
3a & 3b
Periodic Properties of Elements
Alkali Metals
Location: group 1
Characteristic Elements: Na, K, Rb, Cs, Fr
Reactivity: most active metals (Fr is THE most active
metal), never found free in nature, electrolysis of
fused salts.
lo IE & electronegativity
lose e-, IR<AR
Alkaline Earth Metals
Location: group 2
Characteristic Elements: Be, Mg, Ca, Sr, Ba, Ra
Reactivity: very hi, but less than group 1. Also never
found free in nature, electrolysis of fused salts
lo IE & electronegativity
lose e-, IR<AR
Transition Metals
Location: groups 3-12
Characteristic Elements: Fe, Cu, Cr, Au, Ag, Pt, Pb,
Mn, Co…
Special Characteristics: hard solids with hi MP, less
reactive than groups 1 & 2
multiple oxidation states due to more than
one energy level being filled at a time
cause: colored solutions in water
Why do transition metals produce
colored solutions?
MULTIPLE OXIDATION STATES!
Look at:
Fe
Cr
Ni
Cu
Alloy
Def: solid mixture of metals (homogeneous
mixture, ratio can vary)
Examples:
brass – mixture of zinc & copper
bronze – copper & tin
sterling silver – silver & copper
Halogens
Location: group 17
Characteristic Elements: F, Cl, Br, I, At
Reactivity: most reactive NONMETALS, Also never found
free in nature, electrolysis of fused salts or chemically
hi IE & electronegativity (F is highest of 4.0)
gain e-, IR>AR
Exhibit all 3 states of matter (F & Cl (g), Br (l), I & At (s))
Noble Gases
Location: group 18
Characteristic Elements: He, Ne, Ar, Kr, Xe, Rn
Reactivity: monatomic because full valence shell of
8 e- (He is full w/ 2 e-) therefore, do not react
exception: Xe & Ar w/ F
BP increases with increasing size
Use the next slide to label the blank periodic
table found on page 18 of your packet.
Label the name of and color the group(s) as
follows:
ALKALI METALS - RED
ALKALINE EARTH METALS – ORANGE
TRANSITION METALS – YELLOW
METALLOIDS-GREEN
HALOGENS- BLUE
NOBLE GASES - PURPLE
Groups/Families of the Periodic Table
Learning Guide 4:
Families of Elements
1. As you look down a group the electron
configuration gains one more number (ring).
2. As you look down a group the number of
valence electrons stays the same.
3. Elements in the same group have similar
chemicals properties because they have the
same number of valence electrons.
Learning Guide 4:
Families of Elements
4. As you go down a group the elements may
change from nonmetal metalloid  metal.
5. The metallic characteristics increase as you go
down a group.
6. As you go left to right metallic characteristics
decrease.
7. Hydrogen may not be considered a member of
group 1 because it can also acts as a nonmetal in
group 17.
Learning Guide 4:
Families of Elements
8. Hydrogen can have +1 or -1
oxidation states.
9. Hydrogen shares it’s electrons when it combines
with oxygen to form water,.
10. Group 1 is named alkali metals.
11. Group 2 is named alkaline earth metals.
12. Group 1 & 2 elements are characterized by low
electronegativity and high reactivity.
13. Group 1 is more reactive than group 2.
Learning Guide 4:
Families of Elements
14. Groups 14, 15, 16 progress from
nonmetal  metalloid metal.
Learning Guide 4:
Families of Elements
15. Group 17 is named halogens.
16. Group 17 is the only group
that contains solid, liquid and gas. 
17. Group 17 elements combine with
metals to produce HALIDE salts.
18. Group 17elements are characterized
by high EN and high IE.
Learning Guide 4:
Families of Elements
19. Since small nonpolar molecules are held in
solid and liquid phases by very weak forces, BP &
MP increase as the number of electrons increase.
20. Groups 1, 2, & 17 are never found free in
nature because they are too reactive. They will
react with anything in the air quickly.
21. They are reduced to their free state by
electrolysis: zap them w/ lots of electricity!!
Learning Guide 4:
Families of Elements
22.) Elements in groups 1 and 17 always form a
compound with a 1:1 ratio
a.) if Na (group 1) & Cl (group 17) react to form
NaCl,
And K (group 1) & Cl (group 17) will form KCl
b.) They react this way because of their numbers
of valence electrons.
Learning Guide 4:
Families of Elements
23.) Elements in groups 2 and 17 always form a
compound with a 1:2 ratio
a.) if Mg (group 2) & Cl (group 17) react to form
MgCl2,
And Ca (group 2) & Cl (group 17) will form CaCl2
b.) They react this way because of their numbers
of valence electrons.
Learning Guide 4:
Families of Elements
24. Group 18 elements were once called the inert
gas group because they do not react with other
elements, due to a gull valance shell of 8
electrons. They are now called noble gases.
25. The trend in BP going down group 18 is
increasing
(look it up on ref. table S: He BP = 4K
Rn Bp =211 K
Learning Guide 4:
Families of Elements
26.) Exceptions to this naming are the elements
Krypton (Kr) & Xenon (Xe). They can be forced to
react under extreme conditions because they are
so large, with low EN and IE.
Complete chemdo 4
Reactivity of Metals Demo
(pg 21)
Complete the following data table by making observations about
the physical appearance of the metals shown by the instructor.
Include luster(shine), hardness or softness, reaction with air.
Physical properties of group IA & IIA metals
IA (1)
IIA (2)
Na
Mg
K
Ca
Observe the reactions of each metal as the
instructor places it in water. Record your
observations below.
Na
K
Reactivity of group IA (1) & IIA (2) metals in water
IA (1)
IIA (2)
Mg
Ca
Video demos of alkali metals
Video of sodium in water
Video if potassium in water
Video of Cesium in water
Video of Francium in water
Learning Guide 5:
Properties of a group
1. The metals in group 1 are called alkali metals.
2. The metals in group 2 are called alkaline earth
metals.
3. Group 1 and 2 metals easily lose electrons and
they are never found free in nature.
4. Group 1 and 2 typically form ionic bonds in order
to achieve a stable octet of 8 valence electrons.
5. Elements in group 1 & 2 have low IE & low EN.
6. Elements in group 1 form ions with a +1 charge
and elements in group 2 form ions with a -1 charge.
Learning Guide 5:
Properties of a group
7. Reactivity increases as you go down the groups
1 & 2 top to bottom.
8.The most reactive metal is Fr (Francium).
9. Metallic character increases as you go down
groups 14,15, 16. (nonmetal  metalliodmetal)
10. The nonmetals in groups 14, 15, 16 are C, N, P,
O, S, Se.
11. The metalliods in groups 14, 15, 16 are Si, Ge,
As, Sb, Te, Po.
Learning Guide 5:
Properties of a Group
12. The metals in groups 14, 15, 16 are Sn, Pb, Bi,
Po.
13. Group 17 elements are called halogens.
14. Group 17 is special because it has all three
states of matter: solid (I, At), liquid (Br) and gas (F,
Cl.
15. The most reactive element of group 17 is F
(flourine).
Learning Guide 5:
Properties of a Group
16. Group 18 elements are called noble gases.
17. The noble gases used to be called INERT
GASES because they don’t react with other
elements.
18. Because they don’t react with other elements
– they are snobs.
19. Elements in the same group/family have
similar chemical properties because they have the
same number of valence electrons.
Complete Chemdo 5
Never found free in nature: groups 1, 2, 17
Colored ions due to multiple oxidation states: transition metals
Strongest Metal: Fr
Strongest Nonmetal: F
Liquids at RT: Hg & Br
Periodic Table Review
• Trends across a period L  R, due to
increased nuclear charge (val. e- in same
energy level) pulling valance electrons
closer/tighter
– Decreased AR, Increased IE & EN
• Trends down a group (top  bottom), due to
shielding: more energy levels between nucleus
and valence electrons
– Increased AR, Decreased IE & EN