Density

The term density is the mass of a substance per unit volume. The symbol most often used for density is ρ, and sometimes the letter D can also be used. Mathematically, density is defined as mass divided by volume:

ρ = m/V

Where m = mass of the substance, V = volume.

Density is measured in g/cm³ or kg/m³.

The density of a substance is influenced by a variety of factors, such as pressure or temperature. They have little influence for most solid materials, but there's a significant effect on the density of solids and liquids.

Density is calculated depending on the type of material:

• Homogeneous materials: The density at all regions of a homogeneous object equals its total mass divided by its total volume.
• Heterogeneous materials: The density varies between different regions of the object. The density of heterogeneous materials is calculated by determining the densities of many small volumes around various locations of the said material.
• Non-compact materials: Materials such as flakes, pellets, granules or powders contain voids, such as air, water or other fluids. The density of such materials is determined by multiple methods, such as pycnometer method or mathematical expressions for various geometric shapes.

List of densities

Common densities

Material	Density (kg/m3)	Notes
Hydrogen	0.08988 g/L	At 0 °C and 101.325 kPa
Helium	0.1786	At 0 °C and 101.325 kPa
Aerographite	0.2	The air inside is excluded
Metallic microlattice	0.9	Idem
Aerogel	1.0	Idem
Air	1.2	Standard conditions
Tungsten hexafluoride (gas)	12.4	Standard conditions
Liquid hydrogen	70	At –255 °C
Styrofoam	75	Average type of styrofoam
Slush hydrogen	85	At -259 °C
Solid hydrogen	86	At <−259.14 °C
Cork	240	Average type of cork
Pine	373
Lithium	535
Wood	700	Seasoned, typical
Oak	710
Potassium	860
Ice	916.7	At 0 °C
Sodium	970
Water	1,000	At 4 °C
Sea water	1,030
Nylon	1,150
Plastics	1,175	Approx. for PP, PETE and PVC
Glycerol	1,261	Standard conditions
Tetrachloroethene	1,622	Standard conditions
Fuming nitric acid	1,500
Calcium	1,550
Magnesium	1,740
Concentrated sulfuric acid	1,840
Beryllium	1,850
Sulfur (gamma)	1,920
Sulfur (beta)	1,960
Sulfur (alfa)	2,070
Silicon	2,330
Concrete	2,400
Aluminium	2,700
Bromine	3,102.8	Standard conditions
Diiodomethane	3,325
Diamond	3,500
Iodoform	4,008
Carbon tetraiodide	4,320
Titanium	4,540
Tungsten hexafluoride (solid)	4,560	At −9 °C
Selenium	4,800
Iodine	4,933
Germanium	5,323
Vanadium	6,100
Tellurium	6,240
Antimony	6,690
Zinc	7,000
Chromium	7,200
Tin	7,310
Manganese	7,325
Iron	7,780
Niobium	8,570
Brass	8,600
Cadmium	8,650
Cobalt	8,900
Nickel	8,900
Copper	8,940
Bismuth	9,750
Molybdenum	10,220
Silver	10,500
Technertium	11,000
Lead	11,340
Thorium	11,700
Palladium	12,023
Rhodium	12,410
Ruthenium	12,450
Mercury	13,546
Tantalum	16,600
Uranium	18,900
Tungsten	19,250
Gold	19,320
Plutonium	19,840
Rhenium	21,020
Platinum	21,450
Iridium	22,420
Osmium	22,570

Density of materials at different temperatures

Water

Temperature	Density (kg/m3)
+100	958.4
+80	971.8
+60	983.2
+40	992.2
+30	995.6502
+25	997.0479
+22	997.7735
+20	998.2071
+15	999.1026
+10	999.7026
+4	999.9720
0	999.8395
-10	998.117
-20	993.547
-30	983.854

The values below 0 °C refer to supercooled water.