An electric device delivers a current of [tex]$15.0 A$[/tex] for 30 seconds. How many electrons flow through it?
Answer (1)
3-ethylpent-1-yne has a triple bond between the first and second carbons of a 5-carbon chain, with an ethyl group on the third carbon.
The correct structure for 3-ethylpent-1-yne is D.
1-ethyl-2-methylbenzene is a benzene ring with an ethyl group on the first carbon and a methyl group on the second carbon.
The correct structure for 1-ethyl-2-methylbenzene is A.
Explanation
Understanding 3-ethylpent-1-yne Let's break down the structure of 3-ethylpent-1-yne. 'Pent' signifies a chain of 5 carbon atoms. 'yne' indicates the presence of a triple bond. '1-yne' means the triple bond is located between the first and second carbon atoms. '3-ethyl' tells us that an ethyl group ( C H 2 C H 3 ) is attached to the third carbon atom in the chain.
Identifying the Correct Structure for 3-ethylpent-1-yne Now, let's draw the structure:
C H e q u i v C − C H ( C H 2 C H 3 ) − C H 2 − C H 3
Comparing this with the given options, we find that option D matches our structure.
Understanding 1-ethyl-2-methylbenzene Next, let's analyze 1-ethyl-2-methylbenzene. Benzene is a six-carbon ring with alternating single and double bonds. '1-ethyl' means an ethyl group ( C H 2 C H 3 ) is attached to the first carbon atom. '2-methyl' means a methyl group ( C H 3 ) is attached to the second carbon atom.
Identifying the Correct Structure for 1-ethyl-2-methylbenzene Let's draw the structure:
CH2CH3
|
----C----
/ \
C C
| |
C----C----C
\ /
----C----
|
CH3
Comparing this with the given options, we find that option A matches our structure.
Final Answer Therefore, the correct answer for Question 19 is D, and the correct answer for Question 20 is A.
Examples
Understanding the structure of organic molecules like 3-ethylpent-1-yne and 1-ethyl-2-methylbenzene is crucial in fields like pharmaceuticals and materials science. For instance, in drug design, knowing the precise arrangement of atoms in a molecule helps predict its interactions with biological targets. Similarly, in polymer chemistry, the structure of monomers dictates the properties of the resulting polymer. Visualizing and interpreting these structures allows scientists to tailor molecules for specific applications, such as creating more effective drugs or designing new materials with desired characteristics. Accurately identifying and representing these structures ensures clear communication and reproducibility in scientific research and development.
