**Structural Isomers of 3 Degree Amine with Molecular Formula C6H15N**

To determine the number of structural isomers for a 3 degree amine with the molecular formula C6H15N, we need to consider the different ways the atoms can be arranged within the molecule while following the given rules.

**Breaking Down the Molecular Formula:**
- The molecular formula C6H15N indicates that there are 6 carbon atoms, 15 hydrogen atoms, and 1 nitrogen atom in the molecule.
- Since it is a 3 degree amine, the nitrogen atom must be bonded to three alkyl groups.

**Consideration of Alkyl Groups:**
- To create structural isomers, we need to arrange the alkyl groups (methyl, ethyl, propyl, etc.) in different ways around the nitrogen atom.
- The number of structural isomers will depend on the number and arrangement of the alkyl groups.

**Possible Arrangements:**
Considering the molecular formula C6H15N, let's explore the possible arrangements of alkyl groups around the nitrogen atom:
1. Three alkyl groups: In this case, all three alkyl groups will be attached to the nitrogen atom. The remaining carbon atom can form a chain or a ring structure.
2. Two alkyl groups: Here, two alkyl groups will be attached to the nitrogen atom, and the remaining four carbon atoms will form a chain or a ring structure.
3. One alkyl group: In this scenario, one alkyl group will be attached to the nitrogen atom, and the remaining five carbon atoms will form a chain or a ring structure.

**Counting the Isomers:**
1. Three alkyl groups: Let's consider the possible alkyl groups - methyl (CH3), ethyl (C2H5), and propyl (C3H7).
- For methyl groups: (CH3)3N - 1 isomer
- For ethyl groups: (C2H5)2NH - 1 isomer
- For propyl groups: (C3H7)3N - 1 isomer

2. Two alkyl groups: Let's consider the possible alkyl groups - methyl (CH3), ethyl (C2H5), and propyl (C3H7).
- For methyl groups: CH3N(C2H5)2 - 1 isomer
- For ethyl groups: C2H5N(CH3)2 - 1 isomer
- For propyl groups: C3H7N(CH3)2 - 1 isomer

3. One alkyl group: Let's consider the possible alkyl groups - methyl (CH3), ethyl (C2H5), and propyl (C3H7).
- For methyl group: CH3NH(C2H5)2 - 1 isomer
- For ethyl group: C2H5NH(CH3)2 - 1 isomer
- For propyl group: C3H7NH(CH3)2 - 1 isomer

Therefore, the total number of structural isomers for a 3 degree amine with the molecular formula C6H15N is 1 + 1 + 1 + 1 + 1 + 1 = 6 isomers.

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