Magnesium (Mg) VS Calcium (Ca)
A definitive side-by-side comparison of two essential element profiles.
VS
Main Differences
Magnesium (Mg) is an element in the alkaline earth metals category with an atomic number of 12. Calcium (Ca) is an element in the alkaline earth metals category with an atomic number of 20.
Magnesium (Mg) is 1.1x denser than Calcium (Ca). However, Calcium (Ca) melts at a higher temperature than Magnesium (Mg) (a difference of 192.0 Kelvin).
Where do the names come from?
Mg Magnesium (Mg) Naming History
The name Magnesium is derived from Magnesia, a district of Eastern Thessaly in Greece.
Ca Calcium (Ca) Naming History
The name Calcium is derived from the Latin ''calx'' meaning lime.
Related Comparisons
Compare
Magnesium (Mg)
Calcium (Ca)
Category
Alkaline Earth Metals
Alkaline Earth Metals
Atomic Number
12
20
Symbol
Mg
Ca
Atomic Mass
24.305 u
40.078 u
Group
2
2
Period
3
4
Block
s-block
s-block
Standard State (at 20°C)
solid
solid
Density
1.738 g/cm³
1.55 g/cm³
Melting Point (°C)
650°C
842°C
Melting Point (°F)
1202°F
1548°F
Melting Point (K)
923 K
1115 K
Boiling Point (°C)
1090°C
1484°C
Boiling Point (°F)
1994°F
2703°F
Boiling Point (K)
1363 K
1757 K
Year Discovered:
1755
1808
CAS Number
7439-95-4
7440-70-2
Origin of Name:
The name is derived from Magnesia, a district of Eastern Thessaly in Greece.
The name is derived from the Latin ''calx'' meaning lime.