This set of Applied Chemistry Multiple Choice Questions & Answers (MCQs) focuses on “Needs of Green Chemistry”.
1. Green chemistry is also called as ________
a) Life chemistry
b) Environmental chemistry
c) Organic chemistry
d) Sustainable chemistry
Explanation: Green chemistry deals mainly about the pollution variation in environment and sustainance of the plants and animals and mankind in a healthy manner. So, this is also called as the sustainable chemistry.
2. An ideal solvent facilitates the __________
a) Mass transfer
b) Dissolving property
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. A desirable green solvent should be __________
c) Readily available
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. The green solvent maximises the atom _________
a) Molecular weight
b) Electronic configuration
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. 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)
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. The __________ reactions involves reorganisation of the atoms of the molecules.
a) Addition reactions
b) Rearrangement reactions
c) Reorganised reactions
d) Elimination reactions
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. C2H4 +1/2 O2 → C2H4O(Ethylene oxide). This reaction will takes place under presence of catalyst. Find out the %atom economy.
Explanation: Ethylene reacting with oxygen in 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. _________ are greener than the conventional methods.
a) Micro waves
b) Electromagnetic waves
c) Ultra violet waves
d) Radio waves
Explanation: Micro waves are greener than the conventional methods in organic synthesis without solvents. The wide range of the micro wave chemistry is extended recently too many aspects of organic synthesis.
9. Self thermo regulated systems are called as __________
a) Green methodologies
b) Green synthesis
c) Green principles
d) Green concepts
Explanation: The self thermo regulated systems are called as green methodologies. Soluble polymers are another example that comes under green methodologies.
10. _________ 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
Explanation: The yield should be high. This is the 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.
Sanfoundry Global Education & Learning Series – Applied Chemistry.
To practice all areas of Applied Chemistry, here is complete set of 1000+ Multiple Choice Questions and Answers.