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We talked about the state of gas in the chapter. The intermolecular forces that exist between the particles will be discussed in this chapter. The particles are moving away from each other. The temperature of the substance is used to measure the average energy of the molecule. The particles tend to move farther apart as the temperature increases. It is similar to our experience of heating ice and watching it move from the solid state to the liquid state and finally to the gaseous state. The forces between the particles are overcome by the kinetic energy.

The particles are held together by the intermolecular forces in the solid state.

The attractive intermolecular forces are overcome as the temperature increases. The substance will eventually melt, going from solid to liquid state. Even though energy is being added, the temperature remains constant.

As energy is added, the temperature starts to rise again after the solid has been converted into a liquid. The particles have enough energy to move with respect to each other, despite being relatively close together. If enough energy is added, the particles start to break free of the intermolecular forces keeping them relatively close together and they escape the liquid as independent gas particles. Sometimes a solid can go directly from the solid state to the gaseous state without becoming a liquid. Solid carbon dioxide is readily converted to dry ice.

This chapter will show us how to diagram these relationships.

The AP exam for this topic does not include any equations or specific words.

The attractive forces work to overcome the randomizing forces of energy. The structure and type of bonding of a substance have a lot to do with the strength of the interaction. Before we start looking at the different types of intermolecular forces, remember that themolecules that have polar covalent bonding may have positive and negative ends due to charge separation. Intermolecular forces often involve dipoles.

The attraction of an ion and one end of a polar molecule causes these forces.

One of the strongest intermolecular forces is this one.

The intermolecular force requires two different species--an ion and a polar molecule.

The attraction of the positive end of one dipole to the negative end of another is what causes these forces. The hydrogen end has a partial positive charge and the chlorine end has a partial negative charge. Dipole-dipole attractions are important in polar liquids. They are a strong force, but not as strong as ion-dipole attractions.

The attraction of the positively charged hydrogen of one molecule and the negatively charged N, O, or F of another mol ecule is very strong. The hydrogen bonds are stronger than the typical dipole-dipole interaction.

Hydrogen bonding explains why weak acids are weak acids.

It is much harder to break the bonds between the hydrogen of one molecule and the fluorine of another molecule than it is to break the bonds between the hydrogen of both molecule. Water has unusual properties, for example, its high boiling point and the fact that its solid phase is less dense than its liquid phase. The hydrogen bonds keep water from escaping into the gas phase. When water is frozen, the hydrogen bonds lock the water into a framework with a lot of open space. The strands of DNA are held together by hydrogen bonding.

The attraction occurs when the charge on an ion distorts the electron cloud of a nonpolar molecule.

There are two different species of intermolecular forces. They are not very strong interactions.

Only when the other types of intermolecular forces are absent is this attraction significant. The distortion of the electron cloud resulted in the creation of a weak dipole. The weak dipole causes a nonpolar molecule to have a dipole in it. The interaction is weak but strong enough to allow us to liquefy gases such as hydrogen, H2, and nitrogen. It would be possible to liquefy them if there were no intermolecular forces.

Liquid particles are in constant motion. The areas of order that are short-range do not last very long. Particles may form and break apart. A liquid has a volume but no shape. There are three other properties that deserve discussion. The molecule are pulled in many different ways in the body of a liquid. The molecule are pulled into the body of the liquid from the sides and below, not from above. The liquid tries to minimize its surface area by forming a sphere. In a large pool of liquid, the surface behaves as if it has a thin "skin" over it. The attractive forces at the surface need force to be broken. Nonpolar liquids have a lower surface tension than polar liquids.

Strong intermolecular forces tend to have a higher viscosity than weak intermolecular forces. polar liquids have a higher viscosity than non polar liquids. As the temperature increases, the particles' energy increases. This causes a decrease in the amount of liquid. The longer and more complex the molecule, the more contact the particles will have as they slip by each other.

Competition between the intermolecular forces in the liquid and the attractive forces in the tube wall causes it. The higher the level, the stronger the attraction between liquid and tube. Mercury in a glass tube has a low capillary action because it has weak attractions to the walls.

Liquids like water in a glass tube have strong attractions to the walls and will have a high capillary action.

Water has some very unusual properties because of its stronger intermolecular forces. It has the ability to form hydrogen bonds and will cause a lot of sub stances to be dissolved. The thermal properties are due to the strong hydrogen bonding between the water molecule. The water has a high surface tension. Water in ice is held in a rigid, open framework by hydrogen bonds, which makes it less dense than liquid water. The density of the ice increases as the crystal structure breaks and water fills the holes. The density increases to a maximum of 4degC as the particles' energy increases.

Solids may be one of two types. There isn't a lot of regularity in the structure. There could be small areas of order separated by large areas of particles. They are more similar to liquids than to solid objects.

There is no melting point for amorphous solids. As the temperature rises, they get softer and softer. Glass, rubber, and charcoal are examples.

There are several types of unit cells. The most common type is the cubic system.

The noble gases are the only things that form.

Solid methane and water are examples.

The strength of the intermolecular forces is what leads to the high melt ing points. Some salts are examples of ionic solids. Each cation is surrounded by six other cations.

This explains the electrical and thermal properties of metals.

Graphene, diamond, and SiO2 are examples of network particles. The crystal is large.

There are several equilibriums between states of matter, including the one between a liquid and its vapor. The diagram allows us to predict which state of matter a substance will assume.

The diagram has three general areas that correspond to the three states of matter. The line from A to C shows the solid's change in temperature and vapor pressure. The melting point is represented by the A-to-D line. The variation of a liquid's pressure is represented by the A-to-B line.

No matter how much pressure is applied, the gas cannot be put into a liquid.

There is an associated heat of transition for each of the phases. There are many different types of heat, such as fusion, vaporization, and so on.

Phase changes can be affected by the intermolecular forces. The stronger the intermolecular forces present in a liquid, the more energy must be added to convert it into gas. The stronger the intermolecular forces between the gas particles, the easier it will be to condense the gas into a liquid. The stronger the intermolecular forces, the hotter the transition.

Predict which will have the higher boiling point and higher vapor pressure based on intermolecular forces.

The lower boiling point is what Dimethyl ether has.

Water has strong intermolecular hydrogen bonds.

Dipole-dipole is a polar material with weaker intermolecular forces. Water has a lower vapor pressure and higher boiling point because it takes more energy to evaporate it.

Don't confuse the different types of intermolecular forces.

The melting and freezing points are the same.

When a hydrogen atom is directly bonding to an N, O, or F atom, it's called hydrogen bonding.

When moving from one point to another, pay attention to the phases of the substance.

If you are looking at crystal lattice diagrams, be sure to count the particles in all three dimen sions.

To practice for the AP Chemistry exam, use these questions to review the content of this chapter. There are 18 multiple-choice questions that are similar to what you will find on the chemistry section of the AP exam. You can make these questions even more authentic by following the instructions.

You can't use a calculator. The periodic table and equation sheet can be found at the back of the book.

Iron can be composed of macromolecules at low temperatures. The interac is described by strong bonds.

3 is composed of atoms.

Sand is made of SiO2(s). Sulfur dioxide is an ionic solid.

The compounds propanol, CH3CH2CH2OH, compounds of some elements in the nitrogen are part of the family.

NH3 is the only one that has hydrogen bonding.

NH3 is the only one that is water-soluble.

Which compound is expected to form bonds.

The melting point of NaF is (B) Covalent bonds.

The melting point of hydrogen bonds is present.

Which of the following bonds are present?

A sample of a pure liquid is placed in an open container and heated to the boiling point. The boiling point of cium may be increased by which element is more reactive.

Diethyl ether, CH3 CH2OCH2 CH3 is iso 42 degrees. The mers have the same chemical formula.

The surface tension of diethyl ether is lower than that of 1-butanol. The surface tension held together by London dispersion forces is explained by a collection of molecules.

acetic acid is an exception. The heating curve is represented by the above diagram. What is a pure substance?

The answer describes a metallic solid.

The answer describes an ionic solid.

This answer describes bonds. The hydrogen bonding in 1-butanol is solid.

The answer describes a solid made of polar molecules.

There are no compounds that can form hydrogen bonds through water here, so butane is the only one that can lead to ionization.

The carbon atoms are in water.

The only polar molecule is sulfur dioxide, which is about the same as ionic distances.

Hydrogen bonding occurs when hydrogen is the magnitude of the charges. The bond was directly to F, O, and N.

Argon is a noble gas and none of the other gasses in AlN will lead to the greatest attraction bonding choices.

Diamond is a network solid.

The key factors are the atoms.

The bigger the container, the higher the melting points. Higher charges of moles are irrelevant. Higher melting points will be caused by the container being sealed. If this were the key factor, the boiling point, the answer C deals cause an increase in pressure that will increase with size. The boiling point will be lower if the pressure is decreased.

Review the knowledge you need to score high to be the correct answer.

The carbonyl, C-O, and -OH groups have polar molecules. A participate in hydrogen bonds is illustrated by a nonpolar molecule. The dotted lines in the diagram are for a metal called lic solid.

hydrogen bonds can be formed byCompound A.

The hydrogen bonds hold the two compounds together.

The strongest intermolecular melting at C occurs when the solid begins to melt.

You have 15 minutes to answer the question. You can use the tables in the back of the book.

Write an explanation for each of the observations.

Surface tension is caused by strong intermolecular forces between the solution and the glass; these forces are greater than those within the solution.

You have to give yourself 1 point for this answer.

The intermolecular forces of both CCl4 and CBr4 are London dispersion forces. The stronger the London dispersion forces, the greater the surface tension.

You have to give yourself 1 point for this answer.

H2 bonding is a strong form of dipole-dipole force.

Since hydrogen bonding is stronger than normal dipole-dipole forces, it has a higher viscosity.

You have to give yourself 1 point for this answer.

The more energy the molecule has, the lower it is. The material becomes softer and softer until it flows freely.

You have to give yourself 1 point for this answer.

There are points that can be scored.

The state of matter in which a substance exists depends on the strength of the intermolecular forces between the particles.

The melting point is the temperature at which a substance goes from solid to liquid state and is the same as the freezing point.

The boiling point is the temperature at which a substance moves from liquid to gaseous state. This takes place within the body of the liquid, unlike evaporation, which only takes place at the surface of the liquid.

Sublimation is the process of converting a solid to a gas.

The reverse process is deposition.

Changes of state are called phase changes.

Intermolecular forces are caused by full or partial charges. Intermolecular forces are the forces within a molecule.

Ion-dipole intermolecular forces occur.

There are Dipole-dipole intermolecular forces.

There is a hydrogen atom attached to an N, O, or F atom.

There are intermolecular forces between an ion and a nonpolar molecule.

Intermolecular forces between nonpolar molecules are called London (dispersion) forces.

Liquids have surface tension because they have a thin "skin" on their surface due to the attraction of Molecules at the surface of the liquid.

There is little structure in amorphous solids.

There is a lot of structure in the solid state.

The unit cells are ordered by the crystal lattice of the solid.

Know the five types of solid.

The strength of intermolecular forces can be related to phase changes.