Question

The number of tripeptides formed by three different amino acids using each amino acid once is ______.

Answer 1

Correct Answer: 6

Step-by-step Explanation
Consider three different amino acids, denoted as \( A_1 \), \( A_2 \), and \( A_3 \). A tripeptide is a linear sequence of three amino acids, where the order of the amino acids matters. To determine the total number of possible tripeptides, we need to find the number of permutations of the three amino acids.
Number of Permutations
The number of ways to arrange \( n \) distinct items is given by \( n! \). For \( n = 3 \) amino acids:
\[\text{Number of tripeptides} = 3! = 3 \times 2 \times 1 = 6\]
Conclusion
Six different tripeptides can be formed using three different amino acids, where each amino acid is used once.

Answer 2

Given Structures: 

Looking at the image, it appears that the question is related to organic chemistry, particularly to the identification of chemical compounds based on their structural formulas. The structures in the image involve a halogenated compound (chlorine, \( \text{Cl} \)) attached to carbon atoms.

Structure Breakdown:

1. Structure 1: The first compound has a chlorine atom attached to a secondary carbon (which is attached to two other carbons). This compound is likely a secondary alkyl chloride.

2. Structure 2: The second structure is similar to the first one, with the chlorine atom attached to a secondary carbon. This might be another secondary alkyl chloride.

3. Structure 3: The third structure shows a chlorine atom attached to a primary carbon. This makes it a primary alkyl chloride.

4. Structure 4: The fourth structure is very similar to the third one, showing a chlorine atom attached to a primary carbon. This is another primary alkyl chloride.

Correct Answer: The correct answer \( \boxed{6} \) could indicate that there are six potential structural isomers or related compounds with varying positions of the chlorine atom or different orientations in the molecule.

If the question is asking for another type of analysis, or involves nomenclature, please provide the question details for further clarification!

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Mathematical Representation:

The compounds involve the use of chlorine (\( \text{Cl} \)) attached to carbon atoms. Let's represent the possible structures as:

1. The first structure: 
\( \text{C}_2\text{H}_5\text{Cl} \) (Secondary Alkyl Chloride)

2. The second structure: 
\( \text{C}_2\text{H}_5\text{Cl} \) (Another Secondary Alkyl Chloride)

3. The third structure: 
\( \text{C}_3\text{H}_7\text{Cl} \) (Primary Alkyl Chloride)

4. The fourth structure: 
\( \text{C}_3\text{H}_7\text{Cl} \) (Another Primary Alkyl Chloride)

The correct answer is \( \boxed{6} \), indicating the number of possible isomers based on chlorine's position or orientation in these molecules.