Engineering Chemistry Multiple Choice Questions on “Reverse Osmosis”.
1. The basis of reverse osmosis is _____________
a) Osmotic pressure is greater than the hydrostatic pressure
b) Osmotic pressure is equal to the hydrostatic pressure
c) Hydrostatic pressure is greater than the osmotic pressure
d) Osmotic pressure does not exist
Answer: c
Clarification: The basis of reverse osmosis is that the hydrostatic pressure is greater than osmotic pressure. It is a process by which a solvent passes through a porous membrane in the direction opposite to that for natural osmosis when subjected to a hydrostatic pressure greater than the osmotic pressure.
2. Select the incorrect statement from the following option.
a) Osmosis is the phenomenon by virtue of which flow of solvent takes placefrom low concentration to high concentration through a semi-permeable membrane
b) The flow continues till the concentration is equal on both the sides
c) The driving force of osmosis is osmotic pressure
d) Osmosis is used for the treatment of waste water
Answer: d
Clarification: Reverse osmosis is used for the treatment of waste water. All the other options are correct. Osmosis is the phenomenon by virtue of which flow of solvent takes placefrom low concentration to high concentration through a semi-permeable membrane.
3. Semi-permeable membrane is selective membrane which does not permit the passage of dissolved ________ particles.
a) Solvent
b) Solute
c) Anhydrous
d) Saturated
Answer: b
Clarification: Semi-permeable membrane is selective membrane which does not permit the passage of dissolved solute particles. It is a type of biological or synthetic, polymeric membrane that will allow certain molecules or ions to pass through it by diffusion
4. Which of the following is not used for semi-permeable membrane?
a) Polymethyl sulphate
b) Cellulose acetate
c) Polyamide polymer
d) Polymethyl acrylate
Answer: a
Clarification: Polymethyl sulphate is not used for semi-permeable membrane. Cellulose acetate, polyamide polymer and polymethyl acrylate are used as semi-permeable membranes.
5. The pressure which is applied to separate the water from its contaminants is of the order ___________
a) 5-10 kg/cm2
b) 15-40 kg/cm2
c) 50-100 kg/cm2
d) 100-150 kg/cm2
Answer: b
Clarification: The pressure which is applied to separate the water from its contaminants is of the order 15-40 kg/cm2. It does not require very high pressure.
6. The process of reverse osmosis is also known as ___________
a) Hyper-filtration
b) Double-filtration
c) Double-osmosis
d) Hyper-osmosis
Answer: a
Clarification: The process of reverse osmosis is also known as super- or hyper-filtration. It is a process by which a solvent passes through a porous membrane in the direction opposite to that for natural osmosis when subjected to a hydrostatic pressure greater than the osmotic pressure.
7. Which of the following is not an application of reverse osmosis?
a) Desalination
b) Reclamation of minerals
c) For dialysis in hospitals
d) For industrial use
Answer: d
Clarification: Reverse osmosis is not used for industrial purpose. All the other options are correct. It is used for desalination, reclamation of minerals and for dialysis in hospitals.
8. Select the incorrect statement about reverse osmosis from the following option.
a) It is simple and reliable process
b) It is relatively energy efficient
c) It operates at a comparatively high temperature
d) The life of an SPM is about 2 years and it can be easily replaced within a few minutes
Answer: c
Clarification: Reverse osmosis operates at a comparatively low temperature. All the other options are correct. It is simple and reliable process, relatively energy efficient. The life of an SPM is about 2 years and it can be easily replaced within a few minutes.
9. The pH for the potable water should be in the range of ___________
a) 5-6
b) 7-8.5
c) 9-10
d) 12-13
Answer: b
Clarification: The pH for the potable water should be in the range of 7-8.5. It should not be acidic and also should not have a high value of basicity. Hence, it’s value should be in the neutral range.
10. The total hardness of the potable water should be less than ___________
a) 500 ppm
b) 700 ppm
c) 900 ppm
d) 1000 ppm
Answer: a
Clarification: The total hardness of the potable water should be less than 500 ppm. Water having hardness more than 500 ppm is not safe for consumption.