(a) What is the difference between a CFC and an HFC?(b) It is estimated that the lifetime for HFCs in the stratosphereis 2–7 years. Why is this number significant?(c)Why have HFCs been used to replace CFCs? (d) What isthe major disadvantage of HFCs as replacements for CFCs?

(a) What is the difference between a CFC and an HFC?(b) It is estimated that the lifetime for HFCs in the stratosphereis 2–7 years. Why is this number significant?(c)Why have HFCs been used to replace CFCs? (d) What isthe major disadvantage of HFCs as replacements for CFCs?

Chemistry for Engineering Students

3rd Edition

ISBN:9781285199023

Author:Lawrence S. Brown, Tom Holme

Publisher:Lawrence S. Brown, Tom Holme

Chapter11: Chemical Kinetics

Section: Chapter Questions

Problem 11.85PAE

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Question

(a) What is the difference between a CFC and an HFC?
(b) It is estimated that the lifetime for HFCs in the stratosphere
is 2–7 years. Why is this number significant?
(c)Why have HFCs been used to replace CFCs? (d) What is
the major disadvantage of HFCs as replacements for CFCs?

Expert Solution

Step 1

The major difference between CFC and HFC is that CFC indicate a class of compounds which are completely halogenated whereas HFC indicates a class of compounds that are not completely halogenated but contain hydrogen as well.

Step 2

The lifetime of HFCs is 2-7 years which is very less as compared to the lifetime of CFCs which is 100 years. The short persistence of HFCs ensures the safety of the ozone layer. Hence, the lifetime is significant.

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