Leaching of phosphate rock by strong ________ acid produces phosphoric acid?

Percentage of heavy water in ordinary water is around________?

Molten sodium is used as a coolant in a fast breeder reactor, because of its________?

The suitable evaporator for concentration of foaming liquids is a ________ evaporator?

Fire refining process is employed in case of________?

Catalyst is a substance, which ________ chemical reaction?