Calculate the index of hydrogen deficiency for the following molecular formulas and structures.
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Verified step by step guidance

1. Step 1: Understand the concept of the Index of Hydrogen Deficiency (IHD). IHD is a measure of the number of degrees of unsaturation in a molecule. Each degree of unsaturation corresponds to either a double bond, a ring, or a triple bond. The formula for IHD is: IHD = (2C + 2 - H - X + N)/2, where C is the number of carbons, H is the number of hydrogens, X is the number of halogens (like Br), and N is the number of nitrogens.
2. Step 2: Count the number of carbons (C), hydrogens (H), and halogens (X) in the given structure. From the image, the molecule contains 6 carbons, 9 hydrogens, and 1 bromine atom.
3. Step 3: Substitute the values into the IHD formula. Using the formula IHD = (2C + 2 - H - X + N)/2, substitute C = 6, H = 9, X = 1, and N = 0 (since there are no nitrogen atoms in the structure).
4. Step 4: Simplify the equation step by step. First, calculate the numerator: (2 * 6 + 2 - 9 - 1 + 0). Then divide the result by 2 to find the IHD.
5. Step 5: Interpret the result. The IHD value indicates the number of degrees of unsaturation in the molecule, which corresponds to the presence of rings or double/triple bonds. In this case, the structure contains one ring, which contributes to the IHD.

Key Concepts

Index of Hydrogen Deficiency (IHD)

The Index of Hydrogen Deficiency (IHD) is a measure of the degree of unsaturation in a molecular formula. It indicates the number of rings and/or multiple bonds present in a compound. Each double bond or ring contributes one to the IHD, while each triple bond counts as two. The formula for calculating IHD is IHD = (2C + 2 + N - H - X) / 2, where C is the number of carbons, N is the number of nitrogens, H is the number of hydrogens, and X is the number of halogens.

Chemical Structure Interpretation

Understanding chemical structures is crucial for determining the IHD. The structure provides information about the connectivity of atoms, the presence of functional groups, and the overall geometry of the molecule. In the provided image, the presence of a bromine atom and the cyclic structure indicates potential unsaturation, which must be accounted for when calculating the IHD.

Halogens and Their Effect on IHD

Halogens, such as bromine, affect the calculation of the IHD because they can replace hydrogen atoms in a molecular formula. Each halogen atom is treated as if it were a hydrogen atom in the IHD formula. Therefore, when calculating IHD, the presence of bromine in the structure must be included in the count of atoms to ensure an accurate assessment of the compound's saturation level.