Engineering Questions with Answers - Multiple Choice Questions
Applied Chemistry MCQ – Needs of Green Chemistry
1 - Question
Green chemistry is also called as ________
a) Life chemistry
b) Environmental chemistry
c) Organic chemistry
d) Sustainable chemistry
View Answer
Answer: d
Explanation: Green chemistry deals mainly about the pollution variation in the environment and sustainance of the plants and animals and mankind in a healthy manner. So, this is also called as the sustainable chemistry.
2 - Question
An ideal solvent facilitates the __________
a) Mass transfer
b) Dissolving property
c) Combustion
d) Titration
View Answer
Answer: a
Explanation: An ideal solvent facilitates the mass transfer. Water is called as universal solvent. Any solute can be dissolved in water and facilitates for mass transfer.
3 - Question
A desirable green solvent should be __________
a) Costly
b) Toxic
c) Readily available
d) Synthetic
View Answer
Answer: c
Explanation: A desirable green solvent should be readily available. The desirable green solvent should be cheaper. It should be safe and nontoxic. It should be natural.
4 - Question
The green solvent maximises the atom _________
a) Molecular weight
b) Electronic configuration
c) Velocity
d) Efficiency
View Answer
Answer: d
Explanation: The green solvent maximises the atom’s efficiency. For example benzene can be replaced by the toulene, cyclo hexane instead of carbon tetrachloride can be replaced.
5 - Question
What is the percentage atom utilisation?
a) (mole wt of desired product*100)/mole wt of (desired product+total product)
b) (mole wt of desired product*100)/mole wt of (desired product)
c) (mole wt of desired product*100)/mole wt of (desired product+used product)
d) (mole wt of desired product*100)/mole wt of (desired product+by product)
View Answer
Answer: d
Explanation: The percentage atom utilisation is given by (mole wt of desired product*100)/mole wt of (desired product+by product). Here, mole wt indicates the molecular weight. The by product can be used to re generate the reaction.
6 - Question
The __________ reactions involves reorganisation of the atoms of the molecules.
a) Addition reactions
b) Rearrangement reactions
c) Reorganised reactions
d) Elimination reactions
View Answer
Answer: b
Explanation: The rearrangement reactions involve reorganisation of the atoms of the molecules. Because, neither elimination, substitution nor addition of atoms is not taking place. So, the molecule undergoes the rearrangement reactions.
7 - Question
C2H4 +1/2 O2 → C2H4O(Ethylene oxide). This reaction will takes place under presence of catalyst. Find out the %atom economy.
a) 25%
b) 50%
c) 75%
d) 100%
View Answer
Answer: d
Explanation: Ethylene reacting with oxygen in the presence of catalyst forms the ethylene oxide. The %atom economy can be calculated by (formula wt of atoms utilized/formula wt of reactants)*100. The formula weight of the reactants is 44 and atoms utilized are also 44. So, the %atom economy is 100%.
8 - Question
________ are greener than the conventional methods.
a) Micro waves
b) Electromagnetic waves
c) Ultra violet waves
d) Radio waves
View Answer
Answer: a
Explanation: Micro waves are greener than the conventional methods in organic synthesis without solvents. The wide range of micro wave chemistry is extended recently too many aspects of organic synthesis.
9 - Question
Self thermo regulated systems are called as __________
a) Green methodologies
b) Green synthesis
c) Green principles
d) Green concepts
View Answer
Answer: a
Explanation: The self thermo regulated systems are called as green methodologies. Soluble polymers are another example that comes under green methodologies.
10 - Question
_________ is the fundamental advantage of the sono chemistry in organic synthesis without solvents.
a) High yields
b) High energy requirements
c) Use of solvents
d) High wastes
View Answer
Answer: a
Explanation: The yield should be high. This is one of the advantages of the sono chemistry in organic synthesis without solvents. The other fundamental advantages are low energy requirements, no use of solvents and low wastes.