In crystaline solids this value along with the coefficient of thermal expansion can be determined via powder diffraction.  
In crystaline solids this value along with the coefficient of thermal expansion can be determined via powder diffraction.  Its isothermal form ignores the effects of changing temperature, but it is usually measured in its adiabatic form, where changing temperature can cause problems if the material is not degassed.  Its isotropic form can be calculated from Lame's first parameter and two thirds of the shear modulus.  The square root of this quantity over density is equal to the speed of sound in the medium, though this relation fails in anisotropic solids because this value becomes a tensor.  It can be expressed as dee pee over dee rho over rho, though more commonly density is replaced by relative volume change, and it has the same units as Pressure.  For 10 points, name this porperty of a substance which measures its resistance to a change in volume, the reciprocal of compressibility.
In crystaline solids this value along with the coefficient of thermal expansion can be determined via powder diffraction.  
{Bulk Modulus} of Elasticity [prompt on {incompressibility} until the end]