1. 10/7/16 Today we will define and describe energy Warm Up:
Describe the term energy in your own words

2. Chemistry Chapter 2
Energy and Matter

3. Energy
Energy is the capacity to do work or produce heat.

4. Energy Kinetic Energy – Energy of Motion thermal mechanical
Potential Energy – Stored Energy
gravitational
electrical
chemical
Radiant Energy – Light Energy

5. Measuring Energy Common unit – calorie (cal)
calorie - the amount of energy needed to raise one gram of water one degree Celsius
A Food calorie is actually a kilocalorie (Calorie)

6. Conservation of Energy
Law of Conservation of Energy – Energy cannot be created nor destroyed.
In any process, the amount of energy you start with is the same as the amount of energy you end with.
This energy may have changed forms!!!
Potential  Kinetic

7. Energy Crisis
If energy is conserved, how can our planet be “running out of energy”?
Natural resources are converted to other types of energy. We are running out of these natural resources.
Coal, Petroleum, Natural Gas

8. Temperature A measure of kinetic (thermal) energy Hot vs. Cold
What tool do we use to measure temperature?

9. Temperature Scales Fahrenheit vs. Celsius In science we use Celsius
0°C = freezing point of water at sea level
100°C = boiling point of water at sea level
Units are different sizes

10. Temperature Scales
What is 35°C in Fahrenheit?

11. Temperature Scales Celsius vs. Kelvin
Kelvin is based on absolute zero.
Zero on the Kelvin scale is Absolute zero.
Absolute zero – the point at which all atomic motion stops.
Units are the same size

12. K=°C + 273 Temperature Scales Celsius vs. Kelvin
Kelvin is the SI unit for temperature!
K does not use the word degree!
It is 338 Kelvins outside
K=°C + 273

13. K=°C + 273 260=°C +273 -13ºC = °C Temperature Scales
If you measure the temperature to be 260K, what is the temperature in degrees Celsius?
K=°C + 273
260=°C +273
-13ºC = °C

15. Homework
Energy & Temperature Conversions Practice

16. 10/10/16
Today I will determine whether a change is physical or chemical.
Warm up – Your radio says it is 95 degrees out. What is this temperature in the other two scales?

17. Matter Matter is all “stuff”
Matter – anything that has mass and volume

18. Properties
Physical properties – characteristics that can be observed without changing the identity of the substance (looks)
Color, shape, size, density, melting point, state
Chemical properties - characteristics that cannot be observed without changing the identity of the substance (acts)
Flammability, ability to rust, reactivity with air

19. States of Matter Solid – definite shape ; definite volume
Tightly knit particles with very high relative density
Liquid – no definite shape ; definite volume
Particles starting to spread out; high density
Gas – no definite shape ; no definite volume
Particles very far apart; low density
Plasma – inside sun and stars.
Exist only at very high temperatures

20. States of Matter

21. Changes in Matter
Physical Change – changes that do not alter the identity of a substance
Tearing, cutting, painting, changes of state

22. Changes in Matter

23. Changes in state
Changes in state occur due to the kinetic energy of molecules.
Solid  Liquid – melting
Liquid  Solid – solidification
Liquid  Gas – vaporization
Gas  Liquid – condensation
Solid  Gas – sublimation
Gas  Solid – deposition

24. Changes in state
Adding heat or energy makes particles move faster and spread out ( s  l  g )
Removing heat or energy makes particles move slower and clump together ( g  l  s )

25. Changes in Matter
Chemical Changes – changes that do alter the identity of a substance
Rusting, burning, cooking

26. Conservation of Matter
Matter, like energy, is conserved.
Matter can neither be created nor destroyed!
This will play a big role in what we learn this year!

27. Properties
Both chemical and physical changes alter a substances physical properties so it can be difficult to tell the difference between them
Can it be easily reversed?
Most chemical processes cannot be…

28. Indicators of a chemical change
There are several indicators that a chemical change has occurred.
These indicators are not PROOF!
1. Heat or Light

29. Indicators of a Chemical Change
Cont
2. Color Change
3. Gas Bubbles –
Be careful not to mix up with boiling!

30. Indicators of a Chemical Change
Cont
4. Precipitate –
A solid that forms from combining two liquids

31. Homework
2-3 R&R

32. 10/11/16
Today I will demonstrate chemical and physical changes in the lab

33. 10/12/16
Objective – to explain and differentiate between elements and compounds.
Warm Up – Tell if the following are chemical or physical changes:
1. crushing a can
2. burning a log
3. baking bread
4. dying hair

34. Pure Substances
Pure Substance – a substance made up of only one type of material with a unique set of properties
Two types
Element
Compound

35. Pure Substances Element –
A substance that cannot be separated into simpler substances by a chemical (or physical) change.
Smallest particle of matter.
Each unit of an element is called an atom.
Periodic Table of Elements!

36. Pure Substances
Element –
Periodic Table of Elements!

37. Pure Substances Element – Where do elements get their names? People –
Einsteinium, Curium
Places-
Plutonium, Europium, Californium, Berkelium

38. Pure Substances Element – What about their Symbols?
First letter capitalized
Hydrogen (H), Oxygen (O)
Two letters – one capital one lowercase
Aluminum (Al), Chlorine (Cl)
Latin or old words
Sodium (Na) old word natrium
Gold (Au) Latin aurum

39. Pure Substances Compounds– Two or more elements chemically combined
Cannot be separated by physical means
We call each individual combination of atoms a MOLECULE or a FORMULA UNIT !

40. Pure Substances Compounds– What do we call them?
Many different ways to name compounds
For now, If two element names are put together, you can assume it is a compound!
Ex. Aluminum oxide, sodium chloride
Also, some compounds use common names.
Ex. Sugar, water, salt, methane, ammonia

41. Pure Substances
Compounds have unique properties unrelated to the elements in the compound.
Salt – sodium & chlorine (both toxic)
Compounds will always have the same percent proportions.
Water is always 11% hydrogen, 89% oxygen

42. Pure Substances Review
Both Compounds and Elements are referred to as PURE SUBSTANCES.
Pure substance – unique set of chemical and physical properties

43. Matter – anything that takes up space
Pure Substance – made up of only one type of material
Element – composed of one type of atom
Compound– composed of one type of molecule
Examples:
Lead
Oxygen
Silver
Examples:
Water
Sugar
Lithium fluoride

44. Homework
2-4 R&R

45. 10/13/16 Today I will explain and differentiate between mixtures.
Warm Up – Tell if the following are an element or a compound:
1. iodine
2. potassium chloride
3. sugar
4. krypton

46. Mixtures
A mixture is a blend of two or more Pure Substances which can be separated by physical means. Some mixture are easy to see, others look like a single material.
Element (atoms)
Compound (molecules)
Mixture

47. Mixtures
Two types of mixtures 1. Heterogeneous – has visibly different parts.

48. Mixtures a.k.a. - solutions
Two types of mixtures 2. Homogeneous – looks the same throughout
a.k.a. - solutions

49. Separating Mixtures Heterogeneous Manually separate
Decanting – pouring off
Filtration – separates solid from liquid

50. Separating Mixtures Homogeneous
Crystallization (allowing to evaporate)
Distillation – boiling point differences 2 liquids
Fractional distillation – more than 2 liquids
Chromatography– different flows

51. Matter – anything that takes up space
Pure Substance – made up of only one type of material
Mixture – made up of two or more types of materials
Element – composed of one type of atom
Compound– composed of one type of molecule
Homogeneous – same throughout
(AKA Solution)
Heterogeneous – separate parts
Examples:
Lead
Oxygen
Silver
Examples:
Water
Sugar
Lithium fluoride
Examples:
Salt Water
Air
Metal Alloys
Examples:
Muddy Water
Chex Mix
Oil and Water

52. Homework
2-5 R&R

53. 10/14,18/16
Today I will isolate a dye and determine if it is a pure substance or a mixture.

54. 10/20/16 Today I will review chapter 2
Warm Up – Tell if the following are an element, a compound, a homogeneous mixture, or a heterogeneous mixture:
1. bromine
2. salt water
3. water
4. air
5. pepperoni pizza

55. 10/21/16 Today I will review chapter 2
Warm Up – How might you separate a mixture of sand, iron bits and salt?