Solid particles separation based on the difference in their flow velocities through fluids is termed as the________?

Hearth furnaces are not used for________?

Catalyst used in alkylation process is________?

In Hydrofining catalytic desulphurisation process for sweetening of petroleum products, use of hydrogen________?

Main use of hydrazine is________?

Where the density difference of the two liquid phase to be separated is very small (as in milk cream separator), the most suitable separator is a________?