Gypsum is chemically ________?

In a boundary layer developed along the flow, the pressure decreases in the downstream direction. The boundary layer thickness in this case will ________?

For given number of passes, pitch & tube diameter, the maximum number of tubes that can be accommodated in a shell of tripled inside diameter will be ________ times?

________ does not contain copper as an alloying element?

Yield of elemental phosphorous from rock phosphate is about ________ percent?

Vertical condenser is advantageous to the horizontal condenser from operation point of view, when________?