Fluorine (F) VS Chlorine (Cl)

A definitive side-by-side comparison of two essential element profiles.

Main Differences

Fluorine (F) is an element in the halogens category with an atomic number of 9. Chlorine (Cl) is an element in the halogens category with an atomic number of 17.

Chlorine (Cl) is 1.9x denser than Fluorine (F). However, Chlorine (Cl) melts at a higher temperature than Fluorine (F) (a difference of 118.1 Kelvin).

Where do the names come from?

F
Fluorine (F) Naming History

The name Fluorine is derived form the Latin ''fluere'', meaning to flow

Cl
Chlorine (Cl) Naming History

The name Chlorine is derived from the Greek ''chloros'', meaning greenish yellow.

Related Comparisons

Compare

Compare
Fluorine (F)
Chlorine (Cl)
Category
Halogens
Halogens
Atomic Number
9
17
Symbol
F
Cl
Atomic Mass
18.998 u
35.45 u
Group
17
17
Period
2
3
Block
p-block
p-block
Standard State (at 20°C)
gas
gas
Density
1.696 g/L g/cm³
3.214 g/L g/cm³
Melting Point (°C)
−219.67°C
−101.5°C
Melting Point (°F)
−363.41°F
−150.7°F
Melting Point (K)
53.53 K
171.6 K
Boiling Point (°C)
−188.11°C
−34.04°C
Boiling Point (°F)
−306.6°F
−29.27°F
Boiling Point (K)
85.03 K
239.11 K
Year Discovered:
1886
1774
CAS Number
7782-41-4
7782-50-5
Origin of Name:
The name is derived form the Latin ''fluere'', meaning to flow
The name is derived from the Greek ''chloros'', meaning greenish yellow.