Enter the number of carbon atoms, nitrogen atoms, halogen atoms, and hydrogen atoms into the calculator to determine the Index of Hydrogen Deficiency.

Index Of Hydrogen Deficiency Formula

The following formula is used to calculate the Index of Hydrogen Deficiency (IHD).

IHD = (2C + 2 + N - X - H) / 2

Variables:

  • IHD is the Index of Hydrogen Deficiency
  • C is the number of carbon atoms
  • N is the number of nitrogen atoms
  • X is the number of halogen atoms
  • H is the number of hydrogen atoms

To calculate the Index of Hydrogen Deficiency, multiply the number of carbon atoms by 2, add 2, add the number of nitrogen atoms, subtract the number of halogen atoms, and subtract the number of hydrogen atoms. Divide the result by 2.

What is an Index Of Hydrogen Deficiency?

The Index of Hydrogen Deficiency (IHD) is a count of how many molecules of hydrogen a compound is missing compared to the maximum possible number of hydrogen atoms it could contain. It is used in organic chemistry to help identify and classify organic compounds. The IHD can indicate the presence of unsaturated bonds (double or triple bonds) or rings in the molecule, as these features reduce the number of hydrogen atoms a compound can hold.

How to Calculate Index Of Hydrogen Deficiency?

The following steps outline how to calculate the Index of Hydrogen Deficiency (IHD).


  1. First, determine the number of carbon atoms (C).
  2. Next, determine the number of nitrogen atoms (N).
  3. Next, determine the number of halogen atoms (X).
  4. Next, determine the number of hydrogen atoms (H).
  5. Use the formula: IHD = (2C + 2 + N – X – H) / 2.
  6. Finally, calculate the Index of Hydrogen Deficiency (IHD).
  7. After inserting the variables and calculating the result, check your answer with the calculator above.

Example Problem:

Use the following variables as an example problem to test your knowledge.

Number of carbon atoms (C) = 6

Number of nitrogen atoms (N) = 1

Number of halogen atoms (X) = 0

Number of hydrogen atoms (H) = 14