Topic: Chemistry 11/13/15 Aim: How does matter change? Do Now: Work on solubility sheet we labeled as classwork

PHASES OF MATTER 1. SOLID Definite volume & shape Molecules packed together Vibrate in place

Diamonds form under tremendous pressure, and therefore their particles (carbon atoms) are packed very tightly. This is one reason why diamonds are so hard.

2. LIQUID Definite volume No definite shape (shape of container) Loosely packed Slide past each other

3. GAS No definite shape or volume Molecules very far apart & very fast

But what happens if you raise the temperature to super-high levels… between 1000°C and 1,000,000,000°C ? Will everything just be a gas?

4. PLASMA High energy charged particles Sun, fire, lightning, fluorescent & neon lights

Some places where plasmas are found… 1. Flames

2. Lightning

The Sun is an example of a star in its plasma state

Aurora (Northern Lights)

Neon lights

Stars Stars make up 99% of the total matter in the Universe. Therefore, 99% of everything that exists in the entire Universe is in the plasma state.

A plasma TV has a large number of tiny cells containing xenon and neon gases. When an electric current is passed through these individual cells, they give off energy which causes phosphors inside the cell to give off light. These tiny lights combine together to produce an image.

Brainpop Phases of matter

Review: 1.Identify the different phases of matter. 2.Identify the state of matter in which molecules are tightly packed. 3.The particles of a substance that does not have a definite volume or shape is ____. 4.In this phase of matter, atoms or particles are charged and possess a large amount of energy. 5.Describe the atoms/molecules of a liquid.

PHASE CHANGE Absorption or release heat (energy).

2. FREEZING L  S Heat removed/ released Slow down & closer together 1. MELTING S  L Heat added/absorbed Faster & farther apart

Melting point = Freezing Point (different for every substance) MP/FP of water = 0°C

3. EVAPORATION Vaporization/boiling L  G Heat added/absorbed Faster & farther 4. CONDENSATION G  L Heat removed/released Slower & closer

BP of water = 100°C

Evaporation occurs at the surface of a liquid (left). When a liquid boils, gas bubbles form throughout the liquid and then rise out of the liquid (right).

5. SUBLIMATION S  G Heat added/absorbed Dry ice (solid CO 2  gas)

Solid Gas

Example: Iodine crystals  gas (slightly above room temp) Crystals Gas

Moth balls commonly undergo the process of sublimation. Sublimation is the process in which a solid changes directly to its gaseous phase, skipping the liquid phase.

Depostition (G  S) Example: frost

Freezing Melting Evaporation Condensation Add heat  Remove heat  SOLIDLIQUID GAS (faster & farther apart) Energy absorbed by molecules Energy released by molecules (slower down & closer)

Brainpop Phase changes

Review: 1.During what phase changes do molecules absorb heat? 2.During what phases do molecules release heat? 3.State the melting point of ice. 4.What is the boiling point of water?

Topic: Chemistry 11/16/15 Aim: How does matter change? Do Now: TTQA

HEATING AND COOLING When a substance is being heated, you can tell that the particles are absorbing energy by measuring the temperature. For example, as you heat water, you should see a temperature increase as time goes by. But something odd will happen when the water starts to boil…. The temperature will stop increasing!

When water reaches its boiling point, it stays at 100°C until it all changes to steam. Them temperature of the steam can then rise above 100°C.

PHASE CHANGE TEMPERATURE Stays same until all of substance changes Why? Energy needed to change substance, not temperature

Time TEMPTEMP 100°C 0°C PHASE CHANGE GRAPH FOR WATER

Time TEMPTEMP Freezing/melting point = 0°C Boiling pt = 100°C SOLID LIQUID GAS 100°C 0°C Melting Freezing Evaporation Condensation PHASE CHANGE GRAPH FOR WATER = phase changes

The Heating Curve Temperature ( o C) Time (minutes) In this experiment, how long did it take for the water to start boiling? Why didn’t the temperature of the water increase after 4 minutes? How long did it take for all the water to turn into steam? 4 minutes The energy was being used to separate the water molecules and turn the liquid into a gas. 12 minutes w a t e r o n l y water and steam s t e a m o n l y

The Cooling Curve for stearic acid How can we find the freezing point of the acid? Look for where the temperature stops changing. This is where the substance is changing state. The freezing point of stearic acid is 48 o C. If this experiment was continued, the temperature would even off around 20 o C. Why? When the solid stearic acid cooled to room temperature, it would not be able to cool any more. Temperature ( o C) Time (minutes) X X X X XX X X X

REVIEW: 1. When a liquid becomes a solid, energy ____. 2. ____ is the process in which liquid changes to gas below the boiling point. 3. The change of a liquid to a solid is called__. 4. What happens to the position of water molecules as they lose heat energy? 5. Identify one phase change in which energy is released.

PHASE CHANGES SOLIDLIQUID GAS

Time TEMPTEMP 100°C 0°C PHASE CHANGE GRAPH FOR WATER

Solution 1 A. Water condenses at a temperature of 3) 100°C B. At a temperature of 0°C, water 1) freezes2) melts C. When a gas condenses, heat is 1) released D. Freezing is 2) exothermic

Learning Check 2 Is energy absorbed (1) or released (2) in each of the following: ____A. Ice to liquid water ____B. Water vapor to rain ____C. Water to ice When it rains, the air becomes 1) warmer2) cooler3) does not change

Chemical Changes in Matter The rusting of iron is a chemical change. The iron atoms in the nail combine with oxygen atoms from O 2 in the air to make a new substance, rust, with a different composition. 57

CO 2 (s) CO 2 (g) Dry Ice Subliming of Dry Ice Common Physical Changes processes that cause changes in the matter that do not change its composition state changes – boiling/condensing – melting/freezing – subliming Dissolving of Sugar C 12 H 22 O 11 (s) C 12 H 22 O 11 (aq) dissolving 58

Common Physical Changes Dissolving of Sugar C 12 H 22 O 11 (s) C 12 H 22 O 11 (aq) 59

Exit Ticket Jack was eating ice cream outside on a summer day. He noticed that his ice cream was going through a physical change. What type of changes were happening to Jack’s ice cream? What was causing the changes?

Evidence of Chemical Change Bubbles of gas appear A precipitate forms A color change occurs The temperature changes Light is emitted

Create a Venn diagram to compare and contrast physical and chemical properties

Chemical Change Verbs Chemical Change Verbs: rusting, rotting, curdling, burning, cooking, light sensitivity, digesting, tarnishing.

All substances have properties… Including people! Example: People can be identified by their … Face ( shape, expressions ) VoiceHeightFinger prints Eye colorHair colorTeethDNA