Does increasing the amount of mass of the catalyst increase the rate of reaction? I'm not sure as increasing the volume of one reagents doesn't increase the rate of reaction. But for a catalyst I'm not sure if it works the same way. If the catalyst is solid then the concentration will be increased when mass is doubled but for fluid catalysts I'm not so sure. So what affects the rate of a catalysed reaction in terms of the catalyst itself? Thanks for the help!