PERIODIC PROPERTIES
DESCRİPTİON
For the following data, plot the atomic number on the x- axis and the proporty on the yaxis.Each property should be graphed on a separate sheet of graph paper.
ELEMENT
ATOMIC
NUMBER
ATOMİC
RADIUS
(pm)
H
He
Li
Be
B
C
N
O
F
Ne
Na
Mg
Al
Si
P
S
Cl
Ar
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
53
31
167
112
87
67
56
48
42
38
190
145
118
111
98
88
79
71
FIRST
IONIZATION
ENERGY
(kj/mol)
1312
2372
520
899
801
1086
1402
1314
1681
2081
496
738
578
787
1012
1000
1251
1521
ELECTRON
AFFINITY
(kj/mol)
Analysis of the Data
1. Based on your graphs, what is the trend for atomic radius

Across a period?
Atomic radius decreases across a period.

Down a family?
Atomic radius increases down a family.
2. Based on your graphs, what is the trend for ionization energy

Across a period?
-73
0
-60
240
-27
-122
0
-141
-328
0
-53
230
-44
-134
-72
-200
-349
0
ELECTRON
AFFINITY
(Pauling
Units)
2.1
N.A
1.0
1.5
2.0
2.5
3.0
3.5
4.0
N.A
0.9
1.2
1.5
1.8
2.1
2.5
3.0
N.A
Ionization energy increases across a period,exceptions are 2A more than 3A and
4A more than 5A.
1A<3A<2A<5A<4A<6A<7A

Down a family?
Ionization energy decreases down a family.
3. Based on your graphs, what is the trend for electron affinity

Across a period?
Electron affinity increases across a period.

Down a family?
Electron affinity decreases down a family and noble gas do not have electron
affinity.
4. Based on your graphs, what is the trend for electro negativity

Across a period?
Electronegativity increases across a period.

Down a family?
Electronegativity decreases down a family.
5. What can you infer about the relationship between ionization energy and reactivity of
metals?
Metals should be smaller in order to occur reactivity and metals that are more reactive
have less ionization energy than are less reactive.
6. What can you infer about the relationship between electron affinity and reactivity of
nonmetals?
Reactivity of nonmetals is based on electron affinity. Most electron affinity one is the
most reactive.