Solids and Liquids Chapter 13

Kinetic Theory of Matter p104 Warm up: Imagine you could use special glasses that allowed you to see very small particles. Draw a 3 pictures that show how you think molecules are arranged and how they might move in a solid, liquid and gas. Gas Solid Liquid

Kinetic Theory of Gases p104 No attraction to one another and move in straight lines. Change direction only when particles strike each other or container. Movement is random.

Kinetic Theory of Liquids p104 Particles closer together than gases. Particles have some attraction to one another. motion is vibratory

Kinetic Theory of Solids p104 Particles close together and strong attraction Particles occupy a fixed position Moves as a unit around a fixed point.

Facebook profile page p103 We are going to make a facebook profile for the kinetic molecular theory. Its profile needs to contain: Picture of theory friends Username 5-6 status updates relating to the theory.

Properties of Solids p106 Solids Warm up: write 3 facts from the video. All true solids are composed of crystals. Solids have low kinetic energy. They have a definite volume and assume their own shape.

Crystal Structure p106 Crystals are made from unit cells. units are repeated as the crystal grows. The arrangement is determined by the bonds between the particles. There are seven crystal systems or shapes.

Cubic Hexagonal

Allotropes p106 different chemical states of same element in same physical state. EX: Allotropes of carbon are diamonds and graphite. Diamond: cubic lattice held together by strong covalent bonds. Graphite: layers of hexagonal units held together by weak forces.

Diamond Graphite

Amorphous Solids p106 look solid but have no crystal structure. Glass, plastics, and rubber are examples. They have no sharply defined melting point. High viscosity (resistance to flow)

Questions about solids p105 Answer on Left Page: Compare and contrast allotropes and amorphous solids using a venn diagram. If given a sample of material, how would you determine if it was a pure solid or amorphous?

Properties of Liquids p108 Warm up: Suppose you were extremely small and could stand on a water molecule in a glass of water. Someone takes the water and puts it in the freezer. How does what you see and feel and change as a result? Liquids Occupy a definite volume and indefinite shape. Movement is considered fluid. Nonmoving liquids are flat on top.

Surface Tension and Capillary Action p108 Cohesion: when liquid molecules are attracted to other liquid molecules. Adhesion: when liquid molecules are attracted to other materials. On your left Page: On the top half, divide into a right and a left side. On the left draw a cartoon showing cohesion and on the right side draw a cartoon showing adhesion.

Surface Tensionp108 the force at the surface of a liquid due to cohesive forces of the molecules for each other.

Gerris remigis takes a walk

It’s Magic!

Capillary Action p108 related to the adhesive properties of liquids. Liquid molecules are attracted to the straw. As they “climb” up the straw, other molecules follow.(cohesion) It is limited by gravity and the size of the straw

Capillary action p107 Draw the following diagram on your left page. Explain why the water is higher in the thinner tube. (use CREW)

Intermolecular Forces p110 Warm up: Could there be a compressible liquid? Explain using molecules/ atoms in your answer. Also called “Van Der Waals” forces . Strongest in liquids and solids.

Intermolecular forces p110 London Dispersion Force: positive nuclei of one atom attracts the electrons of another. All molecular substances (2nonmetals) exhibit this and it is the weakest.

Intermolecular forces p110 2. Dipole-Dipole interactions: (polar molecules only) positive end of one molecule attracts the negative end of another. second strongest.

Hydrogen bonding p110 3. Hydrogen bonding hydrogen from one molecule attracted to N, O, or F of another molecule. Strongest force.

Phase Changes p112 Warm up: Can a liquid become a solid without changing the temperature? Phase changes are due to changes in temp (which affects kinetic energy), or pressure (how close the molecules are.) Video

(deposition)

Show how the states of matter are affected by in temp and pressure. triple point is where all three states can exist in equilibrium. The points along the lines are where phase changes occur Phase Diagram p112 Melting & freezing Boiling & condensation Sublimation & Frost formation

Phase Diagram for CO2 Is the freezing point the same as the melting point of a substance?

Heating curves In chem textbook, p487-488, draw fig 14-38 on left page on notebook. Then summarize steps A-E.

Equilibrium Equilibrium is the state in a system in which there is no net change in that system. In a state change system, for example, a beaker of water that is closed off will have two phases. 1. Liquid 2. Gas The point at which there is no increase in the gas particles or no increase in the liquid particles is called equilibrium.

Le Chatelier’s Principle If stress is applied to a system at equilibrium, the system will tend to readjust so that the stress is reduced. The stress may be a temperature, pressure, concentration of products or reactants, or other external factors.

H2O (l) H2O (s) If we add heat to this system at equilibrium, what will happen? That’s right! We call that an equilibrium shift to the left because we will form more of substance on the left side of the yield sign. If we place this system in a freezer, what type of equilibrium shift will occur?

Reaction Rate (Keq) To express the reaction rate (Keq) for the equilibrium reactions, we use the general equation: mA + nB  sP + rQ Keq = [P]s[Q]r [A]m[B]n

H2 (g) + I2 (g) 2HI (g) The K for this reaction is: Keq = [HI]2 [H2] [I2] If we had values for these molecules, we would place the values in this equation.

H2 (g) + I2 (g) 2HI (g) EX: Calculate Keq if: H2 = 0.0050 moles I2 = 0.0035 moles HI = 0.0050 moles Keq = [0.0050]2 = [0.0050] [0.0035] 1.4

Crystal Systems EX: Cubic Hexagonal