Specific surface area is a scale - dependent property , with no single true value of specific surface area definable .
Thus quantities of specific property   determined through BET theory may depend on the adsorbate molecule utilized and its adsorption cross section .
Specific surface area is a scale - dependent property , with no single true value of specific surface area definable , and thus quantities of specific surface area determined through BET theory may depend on the adsorbate molecule utilized and its adsorption cross section .