Intermolecular Forces Chapter 10 Review Intermolecular Forces

#1 Explain the difference between intermolecular and intramolecular forces. Which is stronger?

Intramolecular **Stronger** Hold atoms together within a molecule (chem. Bonding: ionic and covalent) Intermolecular Attractive forces between molecules Responsible for many properties of matter (ex. MP and BP)

#2 What is a dipole? Which molecules have the strongest dipole-dipole attractions?

A dipole occurs when two atoms in a molecule have substantially different electronegativity: One atom attracts electrons more than another, becoming more negative, while the other atom becomes more positive. The greater the electronegativity difference (polarity of the bonds), the greater the dipole-dipole attraction

#3 This type of IMF results from the constant motions of electrons and the creation of instantaneous dipoles

London Dispersion Forces

#4 What is the strongest type of intermolecular force? Name the three elements with a great enough electronegativity to form this type of bond.

Hydrogen Bond N, O, F

#5 Compare solids, liquids and gases in terms of : Shape Volume Movement of particles Attraction of particles Closeness of particles

#6 This state of matter occurs at extremely high temperatures and is made up of electrons and + ions

Plasma

#7 List the three part of the KMT.

#8 This is a hypothetical gas that always fits the assumptions of the KMT

Ideal gas

#9 What is pressure a measure of?

Pressure is a measure of the collisions between the molecules and the walls of the container. More collisions, more pressure

#10 This type of collision results in no net loss/gain of energy

Elastic collision

#11 An increase in temperature causes speed of molecules to ______________. An increase in temperature causes pressure to ______________. An increase in the number of molecules causes pressure to ______________.

Increase

#12 Compare Hydrogen gas and Carbon dioxide gas: at the same temperature: Which has the highest speed? Which has the highest KE?

Hydrogen gas is faster (it’s lighter) Both have the same KE

#13 The process by which a gas escapes through a tiny opening is called

Effusion

#14 During what two conditions (found in your notes) do real gases show the greatest deviation from ideal gases?

Low temperature, high pressure

#15 How does water differ from most other substances when comparing the density of its solid and liquid states?

Solid is less dense than liquid

#16 This phenomena is a result of the attraction of a liquid to the surface of a solid, and allows water to rise up thin tubes or fibers

Capillary Action

#17 When there are two or more different molecular forms of the same element in the same physical state, it is an example of an

Allotrope Ex. Diamond and Graphite (both C)

#18 Which would have the highest melting point/boiling point Molecules held together by hydrogen bonds Molecules held together by London dispersion forces Molecules held together by dipole-dipole attractions

Molecules held together by hydrogen bonds

#19 Label each change of state as endothermic or exothermic Freezing Melting Vaporizing Condensation Deposition Sublimation

Freezing - exo Melting - endo Vaporizing - endo Condensation – exo Deposition - exo Sublimation - endo

#20 When two opposing changes occur at equal rates in a closed system, the system is said to be in ____________________

Equilibrium

#21 Which would have a higher vapor pressure, water or alcohol?

Alcohol

#22 the temperature at which the equilibrium vapor pressure equals the atmospheric pressure is called the ________________

Boiling Point

#23 Compare atmospheric pressure and boiling point at high elevations to that at low elevations

At higher elevations, atmospheric pressure is lower, so boiling point is lower, so it takes longer to cook food

#24 What phase change occurs as a substance goes through line ED with increasing temperature? AD? What is the point called where all three phases are in equilibrium?

Sublimation Melting Triple Point