Chemical Equations and Calculations Quiz

The number of independent ways a molecule can move, including translation, rotation, and vibration.

Vibrations that cause the molecule to stretch or compress along the bond axis.

Vibrations that cause the molecule to bend or deform by changing the bond angle.

Vibrations that involve the movement of two identical atoms in opposite directions.

Vibrations that involve the movement of two identical atoms in the same direction.

The speed at which sound travels through a medium, typically around 350 meters per second in air.

The distinct energy levels within a molecule, corresponding to different modes of motion like rotation, vibration, and electronic transitions.

The distance between the nuclei of two bonded atoms in a molecule.

Rules that determine which transitions between energy levels are allowed in spectroscopy.

A constant related to the moment of inertia of a molecule, which depends on the masses of the atoms and the bond length.

The energy of a molecule's rotational state, determined by its moment of inertia and the quantum number J.

The mass that represents the effective mass of a two-body system.

The energy of a harmonic oscillator, dependent on the quantum number U and the oscillator's natural frequency.

The dipole moment of a molecule, where Q is the charge and d is the separation.

The rotational constant, a measure of the rotational inertia of a molecule.

Alternating single and double bonds in a molecule, allowing electrons to move freely across the molecule.

The study of how molecules interact with different types of electromagnetic radiation (like UV, visible, and infrared).

A type of spectroscopy that uses visible light to study the vibrations in molecules.

The internal arrangement of atoms in a molecule, affecting its vibrational and Raman activity.

Molecules with a separation of charge, resulting in a positive and negative end.

Molecules with an even distribution of charge, lacking a positive and negative end.

The specific energy levels that electrons in an atom can occupy.

Raman spectroscopy studies how molecules vibrate and uses this information to identify specific molecules and their chemical groups. This technique focuses on how light interacts with molecules.

A molecule's polarizability is how easily its electron cloud can be distorted by an electric field. This ability influences how strongly it interacts with light in Raman spectroscopy.

The specific pattern of vibrations that a molecule exhibits, which can be detected using spectroscopic techniques.

Polar molecules have a positive and negative end due to uneven electron distribution. This makes them more likely to interact with light in Raman spectroscopy.

Different functional groups within a molecule exhibit unique vibrational patterns, allowing us to identify them using vibrational spectroscopy.

Non-polar molecules have an even spread of electrons, making them less likely to interact with light in Raman spectroscopy compared to polar molecules.

The structure of a molecule's bonds, including stretching and bending, directly affects the observed vibrational spectrum.

The strength of the Raman signal (how bright a line is) is directly related to how easily a molecule's electron cloud distorts - its polarizability.

The way a molecule is arranged (its structure) directly influences its vibrational patterns, which we see in Raman spectra. This helps us understand the types of bonds present.

Analyzing the vibrational spectrum helps us to determine the presence or absence of specific bonds or functional groups in a molecule.

Vibrational modes, especially in symmetrical molecules, can be either symmetric or asymmetric stretching or bending. These modes influence the visibility of specific peaks in the spectrum.

Raman spectra typically show signals between 400 and 4000 cm⁻¹. This range falls within the infrared region, where molecular vibrations are observed.

KBr is often used in IR spectroscopy as it doesn't absorb light in the infrared region. This makes it a suitable sample holder for observing molecular vibrations.

Some symmetrical bonds or vibrations may not show up in the vibrational spectrum due to cancellation of forces.

The number of vibrations a molecule can exhibit is calculated using a specific formula: 3N-6 (for non-linear molecules) or 3N-5 (for linear molecules), where N is the number of atoms in the molecule.

The observed vibration frequencies in the vibrational spectrum are directly related to the energy levels of the molecular vibrations.