Final answer:
The 5th edition of Organic Chemistry by Smith was published in 2020, which is a key resource for Chemistry Advanced Placement Examination and biochemistry studies.
Step-by-step explanation:
The edition of the book Organic Chemistry by Smith that was published in 2020 is the 5th edition. This edition continues to provide a comprehensive understanding of organic chemistry for students and is often used as a resource for those studying for the Chemistry Advanced Placement Examination. It is worth noting that educational resources such as the Practical Manual of Biochemistry by Singh, which is in its 6th edition as of 2009, are also valuable supplements for students in the field of chemistry and related studies.