Question

السؤال 27

1. The water flux of RO membranes ______ as water viscosity lowers.

   		Increases
   		Decreases
   		Alters
   		Fluctuates

السؤال 28

1. RO membranes are made of _______

   		Plastic
   		Cotton
   		Silk
   		Polymer

السؤال 29

1. A reverse osmosis membrane is a semi-permeable membrane that allows the passage of _________

   		Water
   		Dissolved salts
   		Organics
   		Bacteria

Answer 1

Answer 27 INCREASES

EXPLANATION

When the water viscosity is lowered, the water flux of RO membranes increases and the water viscosity is lowered by an increase in temperature. Thus, the higher the temperature better is the flux. The viscosity makes fluid to flow with less velocitiy and when it decreases fluid flows with less Friction and passes faster through RO membrane.

Answer 28 Polymer

Explanation

The highest recommended applied pressure of commercial membranes presently available is 7.0 Mpa; beyond which compaction will start to occur due to the fact that RO membranes are made of polymers.

Answer 29 Water

Semipermeable membrane allows the passage of solvent through it. However it does not allows the passage of solute molecules.

So a reverse osmosis membrane is a semi-permeable membrane that allows the passage of water (solvent) molecules not the majority of dissolved salts, organics, bacteria and pyrogens.