Phosphorus pentoxide can make nitric acid anhydrous, also hydrochloric. Aqua regia being a combination of the two acids, it seems to follow that the addition of phosphorus pentoxide would result in an anhydrous aqua regia? Is this a correct assumption? If it is correct, then would the 'anhydrous aqua regia' be more effective? And would there be any unusual hazards beyond being a more potent form of aqua regia?