Unit 21. How do you know matter is made of particles? 2. What are the particles called?3. What are the particles doing ?4. What happens to the particles during a

phase change?

Unit 2What are some everyday experiences that show matter is composed of particles—write down your ideas to share with the class.

What do you think the name of these particles is?

Unit 21. Proof matter is made of particles

ex: blow air into a balloon and it expandspump up a basketballwindair pressure (yardstick demo)

2. Particles of matter called: ATOMS

Unit 2Matter is made of small particles called atoms and can exist in four forms or states:1. Solid2. Liquid3. Gas4. Plasma

Let’s explore and describe each phase

Unit 2Solid phase:1. Particles are as close together as possible.2. retains a fixed volume and shape

rigid - particles locked into place3. not easily compressible because of little

free space between particles4. does not flow easily 5. rigid - particles cannot move/slide past one

another

Unit 2Arrangement of particles in the solid phase

Unit 2Liquid phase1. assumes the shape of the part of the

container which it occupies 2. particles can move/slide past one another3. not easily compressible because of little

free space between particles4. flows easily because particles can

move/slide past one another

Unit 2Arrangement of particles in the liquid phase

Unit 2Gas phase1. Particles are widely separated2. assumes the shape and volume of its

container3. particles can move past one another4. Compressible, reason: lots of free space

between particles5. flows easily reason: particles can move

past one another

Unit 2Arrangement of gas particles

Unit 2Plasma phase1. Similar to gas phase but particles are

charged2. Electrons have been removed from atom

by addition of energy (heat or electricity)3. Most abundant phase of matter in the

universe4. Example would be fluorescent lights

Unit 2Plasma linkhttps://www.youtube.com/watch?v=AVEGJZxglIg

Unit 2Phase change lab.Follow instructions in your packet.

Unit 2Post phase change lab—cooling curve

A

B C

D

What did you observe in tt at each letter?

Unit 2Post phase change lab—cooling curve

A = only liquid

B C

D

Unit 2Post phase change lab—cooling curve

A = only liquid

B = first solid C

D

Unit 2Post phase change lab—cooling curve

A = only liquid

B = first solid C = last liq

D

Unit 2Post phase change lab—cooling curve

A = only liquid

B = first solid C = last liq

D= only solid

Unit 2Post phase change lab—cooling curve

A = only liquid

B = first solid C = last liq

D= only solid

What do we say is happening to subst. between B and C?

Unit 2a. substance was cooling (losing heat) entire

time.b. Substance should decrease temperature

entire time.

Problem: if substance was cooling why did the temperature stop going down?

Unit 2Material was liquid to begin with, then began to change to solid—called PHASE CHANGE----- this phase change is called:

Freezing or Heat of Solidification-----this happened between letters B---C----- on what is called the plateau (flat portion)-----flat = no change in temperature-----this is then the Freezing Point of the subst.-----but was cooling entire time!! Losing heat!

Unit 2Let’s find the pattern! What happened between pts:A---B

substance was Coolinglose heattemp decreasesall liquid

Unit 2B---C

coolinglose heatfreezing or phase change (solid—liq)

Temp constant—Why?? this is science!! Good labs pose more questions than they answer, it leads to more labs, it leads us to the truth. We will find out in a later lab

Unit 2C---D

coolinglose heattemp decreasesall solid

Unit 2Phase change lab—heating curve

H

F G

E

Now you fill in what would be seen at each letter

Unit 2E = all solidF = first liquid appearsG = last solid goneH = all liquidThe material was being warmed (Heated) the entire time. Between F—G the substance changed phase from solid to liquidCalled: Melting (heat of fusion)Therefore the melting point was = plateau

Unit 2

See anything funny?????That’s right, melting and freezing pts are the same temperature!!!

Unit 2So to melt something heat needs to be addedTo freeze something heat needs to be removedWhat is happening to the particles?When energy added particles move fasterWhen energy removed particles move slower

Called: Kinetic Molecular Theory(KMT)

Unit 2KMT states all matter is made of particles in constant, endless motion. Phase Type of motionSolid vibrateLiquid vibrate, rotate, translateGas vibrate, rotate, translate

Unit 2Motion of particles link:http://www.kentchemistry.com/links/Matter/phases.htm

Unit 2Two more terms you must know:Viscosity and Thermal expansion

Viscosity: ability to flow or pour.

solids = no viscosityliquids = high viscositygases = high viscosity

Unit 2Thermal expansion:

KMT states particles move faster as heat (temperature) increases. Therefore the particles will get farther apart.The volume of the sample will increaseThat’s why a balloon will shrink in the freezer and expand in the oven!I guess density will change as well????

Unit 2Thermal expansion:If a sample is warmed, what will happen to the density ?

Answer choice-----INCREASE or DECREASE??

Unit 2Complete synthesis of slime lab

Unit 2Post synthesis of slime lab

Unit 2Lab: Qualitative description of gas laws

Unit 2Post lab gas laws

Unit 2Complete boyle’s law lab

Unit 2Post Boyle’s law lab

Unit 2Complete worksheet on gas laws

Unit 2Complete lab on physical and chemical properties and changes

Unit 2Physical property:A characteristic that can be measured or observed without changing the nature of the sample.Ex:

color, mass, density, odor, volume

Unit 2Physical change = phase change!Material does not changeDistance between particles changes!Solid------liquid------gasClose---- farther---farthest

Unit 2Chemical change:Only observed if two or more substances mixed together.Evidence = change in color

change in temperatureformation of gas (bubbles, odor)formation of precipitate

(solid from liquid)

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Unit 2

Unit 2

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