Page 7 - Curriculum Visions Dynamic Book

Atomic (proton) number (equivalent to number of electrons). For an explanation, see page 4.
Symbol
Name
Approximate relative atomic mass (approximate atomic weight).Those in parentheses are radioactive.
29
Cu
Copper 64
Chemists used to compare the mass
of an atom of an element with that of hydrogen. Hydrogen has one proton and one electron, and is the lightest of atoms, so the mass of other elements could be given relative to hydrogen: mass of one atom of element ÷ mass of one atom of hydrogen. Nowadays, for accuracy, they compare the mass with that of carbon: mass of one atom of element ÷ mass of 1/12 atom of carbon, and the 162C isotope
is used.The relative atomic mass of iodine, for example, is 127.This means that an atom of iodine is 127 times as heavy as one atom of hydrogen or 1/12 atom of carbon.
The figures used in this book are approximate and so are correctly referred to as the approximate relative atomic mass (the old term used was atomic weight). They are shown underneath the name
of each element in the Periodic Table.
RELATIVE ATOMIC MASS
3 4 5 6 78or0
(9) (10) (11) (12) (13) (14) (15) (16) (17) (18)
um
m
m )
567
BCN
Boron Carbon Nitrogen 11 12 14
13 14 15
Al Si P
Aluminium Silicon Phosphorus 27 28 31
31 32 33
Ga Ge As
Gallium Germanium Arsenic 70 73 75
49 50 51
In Sn Sb
Indium Tin Antimony 115 119 122
81 82 83
Tl Pb Bi
Thallium Lead Bismuth 204 207 209
Ununquadium (289)
114
Uuq
8 9 10
O F Ne
Oxygen Fluorine Neon 16 19 20
16 17 18
S Cl Ar
Sulphur Chlorine Argon 32 35 40
34 35 36
Se Br Kr
Selenium Bromine Krypton 79 80 84
52 53 54
Te I Xe
Tellurium Iodine Xenon 128 127 131
84 85 86
Po At Rn
Polonium (209)
Ununhexium (289)
Astatine (210)
Radon (222)
Ununoctium (293)
116
118
Uuh
Uuo
ium
m )
61
Pm
Promethium (145)
Neptunium (237)
93
Np
62
Sm
Samarium 150
94
Pu
Plutonium (244)
63
Eu
Europium 152
Americium (243)
95
Am
64
Gd
Gadolinium 157
Curium (247)
96
Cm
65
Tb
Terbium 159
Berkelium (247)
97
Bk
66
Dy
Dysprosium 163
98
Cf
Californium (251)
67
Ho
Holmium 165
99
Es
Einsteinium (252)
68
Er
Erbium 167
100
Fm
Fermium (257)
69
Tm
Thulium 169
101
Md
Mendelevium (258)
70
Yb
Ytterbium 173
102
No
Nobelium (259)
2
He
Helium 4
27 28 29 30
e Co Ni Cu Zn
Cobalt Nickel Copper Zinc 59 59 64 65
45 46 47 48
u Rh Pd Ag Cd
Rhodium Palladium Silver Cadmium 1 103 106 108 112
77 78 79 80
s Ir Pt Au Hg
Iridium Platinum Gold Mercury 0 192 195 197 201
8 109 110 111 112
5
d
4
U
Meitnerium (266)
Ununnilium (272)
Unununium (272)
Ununbium (277)
s Mt Uun Uuu Uub
8
7