Final answer:
The IR spectrum for CH bonds associated with sp3-hybridized carbon displays stretching vibrations in the range of 2850 to 3000 cm-1, representing various CH stretching vibrations in molecules with tetrahedral geometry and sp3-s sigma bonds.
Step-by-step explanation:
The Infrared (IR) spectroscopy of CH bonds for sp3 (single bonds) is characterized by absorbance due to the stretching vibrations of the CH bonds. Typically, in an IR spectrum, these CH stretching vibrations for sp3-hybridized carbon atoms occur in the range of approximately 2850 to 3000 cm-1. This region is noted for saturated hydrocarbons, such as alkanes, where each carbon is bonded to four atoms in a tetrahedral geometry, often resulting in a variety of peaks within that range due to different types of CH stretches (symmetric and asymmetric stretching of CH3 and CH2 groups).
Methane (CH4) is an example where the formation of the molecule involves the overlap of four sp3 orbitals of carbon with the 1s orbitals of hydrogen atoms, forming sp3-s sigma bonds. The result is a molecule with an equal bond length of approximately 108.70 pm and bond angles of 109.5°, constituting a perfect tetrahedral shape. The IR spectrum of methane would show peaks corresponding to C-H stretching vibrations in the aforementioned range.