Element Symbol
Protons
Neutrons
Mass Number
Element Family
100

Rubidum

Rb

100

Helium

2

100

Carbon

6

100

Hydrogen

`

100

Lithium

Alkali Metals

200

Arsenic

As

200

Barium

56

200
Phosphorus

16

200

Carbon

12

200

Xenon

Nobel Gasses

300

Gold

Au

300

Ruthenium

44

300

Zinc

35

300

Sulfur

32

300

Calcium

Alkaline Earth Metals

400

Silver

Ag

400

Moscovium

115

400

Copernicium

173

400

Tungsten

184

400

Uranium

Actinide Series

or

Transition Elements

500

Iron

Fe

500

Actinium

89

500

Holmium

98

500

Samarium

150

500

Silicon

Metalloids

M
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