1. The process of removal of hardness of water, irrespective of whether it is temporary or permanent is termed as __________
a) Cleansing action of water
b) Hardness of water
c) Softening of water
d) Purity of water
Explanation: The process of removal of hardness of water, irrespective of whether it is temporary or permanent is termed as softening of water. This process includes both temporary as well as permanent hardness.
2. The external treatment of water does not include __________
a) Lime-soda process
b) Sequestration
c) Zeolites
d) Ion-exchange process
Explanation: The external treatments of water include lime-soda, zeolites and ion-exchange processes. It does not include sequestration.
3. Which of the following conditioning method is not used in internal treatment?
a) Colloidal
b) Calgon
c) Carbonate
d) Bicarbonate
Explanation: Colloidal, calgon, phosphate and carbonate conditioning methods are used in internal treatment. Bicarbonate is not used for this purpose.
4. Select the incorrect statement from the following option.
a) Internal treatment is carried out outside the boiler before water enters into the boiler
b) Internal treatment methods are followed by blow-down operations
c) Internal treatment is required in low pressure boilers
d) Internal treatment is a corrective method
Explanation: Internal treatment is carried out inside the boiler. All the other options are correct.
5. External treatment is a preventive method and it is required in high pressure boilers.
a) True
b) False
Explanation: External treatment is a preventive method and it is required in high pressure boilers. External treatment is carried out outside the boilers.
6. Potable water treatment does not involve __________
a) Disinfection
b) Demineralisation
c) Coagulation
d) Sedimentation
Explanation: Potable water treatment does not involve demineralisation. It involves disinfection, coagulation and sedimentation processes.
7. The exhausted anion exchangers can be regenerated by working with __________
a) Acid solution
b) Alcohol solution
c) Alkali solution
d) Water
Explanation: The exhausted anion exchangers can be regenerated by working with alkali solution because alkali solution or basic solution does not contain reactive ions.
8. Optical activity is the property in which a substance is unable to rotate the plane of polarisation.
a) True
b) False
Explanation: Optical activity is the property in which a substance is able to rotate the plane of polarisation of plane polarised light.
9. Select the incorrect statement from the following option.
a) Racemic modification is an equimolar mixture of dextrorotatory and levorotatory isomers
b) Meso compounds contain more than one chiral carbon centre
c) Meso compounds are externally compensated
d) Racemic mixture is designated as dl-pair
Explanation: Meso compounds are internally compensated form whereas racemic mixtures are externally compensated modification. All the other options are correct.
10. Select the correct statement from the following option.
a) Meso compound possess both plane of symmetry and centre of symmetry
b) Meso compound possess either plane or centre of symmetry
c) Meso compound does not possess either plane or centre of symmetry
d) Meso compounds are externally compensated form
Explanation: Meso compound possess either plane or centre of symmetry. They do not possess both plane of symmetry and centre of symmetry and also they are internally compensated form.