Deca=Ten
Decade
Decagram
Decadence
Deca=Ten
Nona=Nine
Nonabrasive
Nonastract
Nonaccural
Nona=Nine
Octo=Eight
Octogon
Octopus
October
Octo=Eight
Hept=Seven
Heptachlor
Heptagon
Heptameter
Hept=Seven
Hex=Six
Hexagon
Hexachord
Hexadecimal
Hex=Six
Penta=Five
Pentagon
Pentacle
Pentagonal
Penta=Five
Tetra=Four
Allotetraploid
Autotetraploids
Tetracaine
Tetra=Four
Tri=Three
Triple
Tricycle
Triangle
Tri=Three
Di=Two
Absurdist
Abdicable
Aboding
Di=Two
Mono=OneMonopoly
Ammono
Kimono
Mono=One
Calcium
20
Ca
Neon
10
Ne
Potassium
19
K
Fluorine
9
F
Argon
18
Ar
Oxygen
8
O
Chlorine
17
Ci
Nitrogen
7
N
Sulfur
16
S
Carbon
6
C
Phosphorus
15
P
Boron
5
B