In electromagnetism, **charge density** is a measure of electric charge per unit volume of space, in one, two or three dimensions. More specifically: the linear, surface, or volume charge density is the amount of electric charge per unit length, surface area, or volume, respectively. The respective SI units are C·m−1, C·m−2 or C·m−3.

Like any density, charge density can depend on position, but because charge can be negative - so can the density. It should not be confused with the charge carrier density, the number of charge carriers (e.g. electrons, ions) in a material per unit volume, not including the actual charge on the carriers.

In chemistry, it can refer to the charge distribution over the volume of a particle; such as a molecule, atom or ion. Therefore, a lithium cation will carry a higher charge density than a sodium cation due to the lithium cation's having a smaller ionic radius, even though sodium has more electrons (11) than lithium (3).

Read more about Charge Density: Free, Bound and Total Charge, Homogeneous Charge Density, Discrete Charges, Relative Charge Density, Charge Density (quantum Mechanics), Application

### Other articles related to "charge density, charge, density, charges":

**Charge Density**- Application

... The

**charge density**appears in the continuity equation for electric current, also in Maxwell's Equations ... source term of the electromagnetic field, when the

**charge**distribution moves this corresponds to a current

**density**...

**Charge Density**

... “hump” occurs at the bond site in the

**charge density**... However, the singlet state of C2 acts more like silicon or germanium that is, the

**charge density**has a maximum at the bond site ...

... varies along the conductor's length,

**charge**is uniformly distributed along its circumference (owing to the skin effect) and the electric field is perpendicular to the surface ... Furthermore, only the

**charge**in a neighborhood around any point on the conductor significantly contributes to the electric potential at that point ... the geometry is, effectively, one of an infinitely long conductor with a constant surface

**charge density**(

**charge**per area), thereby reducing a three-dimensional problem to a two-dimensional one ...

... For illustration, figure 1 shows a simple picture of bond

**charges**near the surface of a 2-dimensional crystal with

**charge**(election)

**density**around sphere atoms ... The loss of neighbors which results from the creation of a metal surface reduces the local electron

**density**around the atoms near the surface ... Surface atoms then sit in a lower average electron

**density**than bulk atoms ...

... Continuity equation Vector calculus can be used to express the law in terms of

**charge density**ρ (in coulombs per cubic meter) and electric current

**density**J (in amperes per ... The term on the right is the divergence of the current

**density**J ... equation equates these two factors, which says that the only way for the

**charge density**at a point to change is for a current of

**charge**to flow into or out of the point ...

### Famous quotes containing the word charge:

“To fight aloud is very brave,

But gallanter I know,

Who *charge* within the bosom

The Cavalry of Woe.”

—Emily Dickinson (1830–1886)