Question

How many structural isomers are there for a fivemember straight carbon chain with one double bond? For a six-member straight carbon chain with two double bonds?

Short answer

There are four structural isomers for a five-member straight carbon chain with one double bond, and six structural isomers for a six-member straight carbon chain with two double bonds.

Step-by-step solution

Write the molecular formula.

For a five-member straight carbon chain with one double bond, the molecular formula will be C5H10.

Identify the double bond location possibilities.

Now we need to find the possible locations for the double bond. Starting with the first carbon atom as C1 and continuing to the fifth carbon atom as C5, we can place the double bond between C1-C2, C2-C3, C3-C4 or C4-C5.

List the structural isomers.

The structural isomers with the given molecular formula and observed double bond arrangements are: 1. C1-C2 double bond: (CH2=CH)(CH2)(CH2)(CH3) 2. C2-C3 double bond: (CH3)(CH=CH)(CH2)(CH3) 3. C3-C4 double bond: (CH3)(CH2)(CH=CH)(CH3) 4. C4-C5 double bond: (CH3)(CH2)(CH2)(CH=CH)

Count the structural isomers.

Since we have found four different structural isomers, there are four structural isomers for a five-member straight carbon chain with one double bond. #Case 2: Six-member straight carbon chain with two double bonds.#

Write the molecular formula.

For a six-member straight carbon chain with two double bonds, the molecular formula will be C6H10.

Identify the double bond location possibilities.

To find the possible locations for the double bonds, let's label the carbons again from C1 to C6. Since two double bonds must be placed, we will have the following options: 1. Double bonds between C1-C2 and C3-C4 2. Double bonds between C1-C2 and C4-C5 3. Double bonds between C1-C2 and C5-C6 4. Double bonds between C2-C3 and C4-C5 5. Double bonds between C2-C3 and C5-C6 6. Double bonds between C3-C4 and C5-C6

List the structural isomers.

The possible structural isomers are: 1. C1-C2 and C3-C4 double bonds: (CH2=CH)(CH2=CH)(CH2)(CH3) 2. C1-C2 and C4-C5 double bonds: (CH2=CH)(CH2)(CH2=CH)(CH3) 3. C1-C2 and C5-C6 double bonds: (CH2=CH)(CH2)(CH2)(CH=CH) 4. C2-C3 and C4-C5 double bonds: (CH3)(CH=CH)(CH2=CH)(CH3) 5. C2-C3 and C5-C6 double bonds: (CH3)(CH=CH)(CH2)(CH=CH) 6. C3-C4 and C5-C6 double bonds: (CH3)(CH2)(CH=CH)(CH=CH)

Count the structural isomers.

Since we have found six unique structural isomers, there are six structural isomers for a six-member straight carbon chain with two double bonds.