The bond that gives the most intense band in the infrared spectrum for its stretching vibrations is the OH bond.

Explanation:

- Infrared spectroscopy is a technique used to identify and analyze the functional groups present in a molecule by measuring the absorption of infrared radiation by the sample.
- When a molecule absorbs infrared radiation, it causes the bonds to vibrate and stretch. The frequency of the vibration is related to the strength of the bond and the mass of the atoms involved.
- The stretching vibrations of the OH bond are known to give rise to the most intense band in the infrared spectrum due to the following reasons:
- The OH bond is polar, and it has a large dipole moment. This dipole moment makes the bond more susceptible to infrared radiation absorption.
- The OH bond is relatively weak compared to other bonds, such as CH and NH bonds. Therefore, it requires less energy to stretch and vibrate, making it more likely to absorb infrared radiation.
- The OH group is present in many important functional groups, such as alcohols, phenols, and carboxylic acids. Therefore, the intense band in the infrared spectrum due to OH stretching vibrations can be used to identify these functional groups in a molecule.
- In addition, the position and shape of the OH band in the infrared spectrum can provide information about the hydrogen bonding and the environment surrounding the OH group.

In conclusion, the OH bond gives the most intense band in the infrared spectrum for its stretching vibrations due to its polarity, weak strength, and prevalence in important functional groups.