London Dispersion Forces

Mr. Andersen explains London dispersion forces, a type of intermolecular force present in all atoms and molecules. These forces arise from temporary dipoles created by uneven electron distribution. Factors like contact area, polarizability, and pi bonding influence their strength. Examples include noble gases and hydrocarbons. Understanding these forces helps explain states of matter and molecular interactions.

Who first identified London dispersion forces?

• Isaac Newton

• Fritz London

• Albert Einstein

• Marie Curie

What causes the formation of temporary dipoles in molecules?

• Even distribution of protons

• Stable molecular structure

• Uneven distribution of electrons

• Constant temperature

Why are London dispersion forces crucial for noble gases?

• They stabilize the gas at high temperatures

• They increase the atomic number

• They reduce the atomic mass

• They allow noble gases to exist in a liquid phase

What happens to electrons when two helium atoms come close together?

• They migrate and create temporary dipoles

• They form a permanent bond

• They repel each other

• They remain stationary

Which factor does NOT increase London dispersion forces?

• Higher polarizability

• Increased contact area

• More pi bonding

• Decreased molecular size

How does the structure of n-pentane affect its boiling point compared to neopentane?

• It has a spherical shape, leading to a higher boiling point

• It has fewer electrons, leading to a lower boiling point

• It has more surface area, leading to a higher boiling point

• It has less surface area, leading to a lower boiling point

What is polarizability in the context of London dispersion forces?

• The temperature stability of a molecule

• The rigidity of a molecule

• The squashiness of a molecule

• The ability of a molecule to conduct electricity