Mass action law for semiconductor

[hak555]

For Mass action law to hold for extrinsic material in equilibrium,
If n goes up and p goes down for an N-type material then overall carrier concentration is the same (equal to ni_square). So why does an N-type material conducts better than a an intrinsic semiconductor (presumably they have same number of carriers) at room temperature?

 

[meBigGuy]

https://en.wikipedia.org/wiki/Electron_mobility

Electron and hole mobility are different. Is that what you are asking?