Phosphorus (P) is diffused into a thick slice of silicon with previous phosphorus concentration 11016 atoms/cm3 in it at a temperature of 1100C. If the surface concentration of the phosphorus is 51018atoms/cm3 , and its concentration at 2m is 11017 atoms/cm3 , how long must be the diffusion time? D=310-13cm2 /s for P diffusing in Si at 1100C.

Ahypothrticalax type of ceramic material is known to have a density of 2.10 g/cm3 and a unit cell of cubic symmetry with a cell edge length of 0.57 nm. the atomic weights of the a and x elements are 28.5and 30.0 g/mol, respectively. on the basis of this information, which of the following crystal structures is (are) possible for this material: sodium chloride, cesium chloride, or zinc blende

What is the molar mass of a gas that has density of 2.054 g/l

In which reaction is precipitation occurring?