Module-1
It is a branch of chemistry which deals with study of inter conversion of chemical energy to electrical energy and vice versa.
What is Electrochemistry?
Ans : D
Explanation: Corrosion is a natural process that converts a refined metal into a more chemically stable form such as oxide, hydroxide, or sulfide. It is the gradual destruction of materials (usually a metal) by chemical and/or electrochemical reaction with their environment. Corrosion engineering is the field dedicated to controlling and preventing corrosion.
Which of the following is true about Corrosion?
A. Corrosion is a natural process that converts a refined metal into a more chemically stable form
B. It is the gradual destruction of materials (usually a metal) by chemical and/or electrochemical reaction with their environment
C. Corrosion engineering is the field dedicated to controlling and preventing corrosion
D. All of the above
Answer: (d) thermosetting
akelite is an example of
(a) elastomer
(b) fibre
(c) thermoplastic
(d) thermosetting
Answer: b
Explanation: Ethanal can be prepared by oxidation of ethene, in the presence of an ionic catalyst in an aqueous medium. This is a greener method and gives 90% of yield.
1. Which of the following is a greener route to produce ethanal commercially?
a) Catalytic cracking of ethanol
b) Oxidation of ethene with an ionic catalyst
c) Steam reforming of methanol
d) Dehydrogenation of ethylene
Answer: c
Explanation: Hardness of water is due to the presence of salts of calcium and magnesium. Hard drinking water may have moderate health benefits, but can pose serious problems in industrial settings, where water hardness is monitored to avoid costly breakdowns in boilers, cooling towers, and other equipment that handles water.
1. Hardness of water is due to the presence of salts of ____________
a) Potassium
b) Chlorine
c) Magnesium
d) Boron
C. Ampere hour rating
The capacity of a battery is expressed in terms of
A. Current rating
B. Voltage rating
C. Ampere hour rating
D. None of the above
1.(B)
1-The precision surface finishing operations, employed for producing extremely high surface finish, are called
(A) Macro finishing operations
(B) Micro finishing operations
(C) Precise finishing operations
(D) All of the above
Answer: d
Explanation: Artificial Nanomaterials can be divided into four categories – Carbon-based, metal-based, dendrimers and composites. The other types of nanomaterials are called natural nanomaterials.
1. The four types of Artificial nanomaterials are __________
a) Carbon-based, non-metallic, composites and ceramics
b) Carbon-based, metallic, composites and ceramics
c) Carbon-based, non-metallic, composites and dendrimers
d) Carbon-based, metallic, composites and dendrimers
Answer: c
Explanation: Tetrachloroethene was used as a solvent for dry cleaning purposes. It is a suspected carcinogen and groundwater contaminant. It is replaced by greener solvent like supercritical CO2.
1.Name the conventional solvent that was used for dry cleaning purposes which later confirmed to be a suspected carcinogen.
a) Supercritical CO2
b) Phenanthrene
c) Tetrachloroethene
d) Benzene aldehyde
Answer: d
Explanation: Due to the presence of dissolved hardness-producing salts, the boiling point of water is elevated. Elevation in boiling point is one of the most important colligative property. All the other options are correct.
1. Select the incorrect statement from the following option.
a) Water which does not form lather with soap and forms white scum is called hard water
b) Hard water contains dissolved calcium and magnesium salts in it
c) In hard water, cleansing quality of soap is depressed
d) Due to the presence of dissolved hardness-producing salts, the boiling point of water is depressed
Answer: a
Explanation: Fuel cells are the devices which convert the energy produced during the combustion of fuels (chemical energy) like hydrogen, methane, methanol etc. directly into electrical energy. Hence, a fuel cell is a type of electrochemical cell.
1. A fuel cell is a type of electrochemical cell.
a) True
b) False
Ans : C
Explanation: Galvanic corrosion occurs when two different metals have physical or electrical contact with each other and are immersed in a common electrolyte, or when the same metal is exposed to electrolyte with different concentrations.
1.Which corrosion occurs when two different metals have physical or electrical contact with each other and are immersed in a common electrolyte?
A. Intergranular
B. Crevice
C. Galvanic
D. Erosion
Answer: (b) Styrene
Question .
The S in buna-S refers to
(a) Sulphur
(b) Styrene
(c) Sodium
(d) Salicylate
Answer: c
Explanation: Synthetic methods should avoid using or generating substances toxic to humans and/or the environment. Hence less hazardous chemical synthesis is an important principle.
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Which of the following is not a principle of Green Chemistry?
a) Green solvents and auxiliaries
b) Use of renewable feedstock
c) Hazardous chemical synthesis
d) Design for energy efficiency
Answer: b
Explanation: Unlike temporary hardness, permanent hardness is not destroyed on boiling. Varoius methods are adopted for the removal of permanent hardness like zeolites, lime-soda process etc. All the other options are correct.
1.select the incorrect statement from the following option.
a) Permanent hardness is due to dissolved chlorides and sulphates of calcium and magnesium
b) It can be removed by mere boiling of water
c) It is also known as non-alkaline hardness
d) The difference between the total hardness and the alkaline hardness gives the non-alkaline hardness