1. Matter & Energy Key vocabulary
Chemistry – the study of matter
Matter – (1) Anything which has mass and takes up space
(2) Anything with the property of inertia
Inertia – the tendency to resist a change in motion.

2. PHYSICAL AND CHEMICAL CHANGES
Laws of Conservation…
Law of Conservation of Matter – matter cannot be created nor destroyed, but may change form.
Law of Conservation of Energy – energy cannot be created nor destroyed, but may change form.
THESE TWO LAWS
ARE IN EFFECT IN ALL
PHYSICAL AND CHEMICAL CHANGES

3. Laws of Conservation…
Law of Conservation of Mass-Energy – the total sum of mass and energy in the universe is constant. Matter can be converted to an equal amount of energy and vice versa according to E=mc2.
THIS LAW REPLACES
THE PREVIOUS TWO LAWS
IN NUCLEAR CHANGES

4. Universe Energy Matter Kinetic Potential Mixture Substance KE = ½ mv2
Energy of Motion
Stored Energy
KE = ½ mv2

5. Key Vocabulary
Energy – the ability to do work Substance – matter with fixed composition Mixture – two or more substances with variable composition.

6. Universe Energy Matter Kinetic Potential Mixture Atom Substance
Heterogeneous
Homogeneous (uniform)
Homogeneous (identical)
Energy of Motion
Stored Energy
KE = ½ mv2
Element
Compound
Solution
Atom
Molecule
Symbol
Formula

7. Key Vocabulary
Element – matter made of one type of atom Compound – two or more elements combined in a fixed ratio Solution – two or more substances uniformly mixed (a homogeneous mixture)

8. Universe Energy Matter Kinetic Potential Mixture gold iron rust Atom
Substance
Mixture
Heterogeneous
Homogeneous (uniform)
Homogeneous (identical)
Energy of Motion
Stored Energy
KE = ½ mv2
Mixture
Element
Compound
Solution
Suspension
gold
iron
methane
rust
Atom
Molecule
Colloid
neon
zinc
salt
water
Symbol
Formula

9. Key Vocabulary
Mixture – This term will be used from now on to refer to a Heterogeneous mixture. Suspension – special type of mixture that appears to the naked eye as a solution, but has particles that will settle out over time (Tyndall Effect – a suspension will scatter light from a beam travelling through it, but a solution will not. DEMO) Colloid– like a suspension, but with smaller particles which will not settle out over time (gels, creams and pastes fall into this category.)

10. Key Vocabulary
Phase – a region with a uniform set of properties (Elements, compounds and solutions contain only one phase, but mixtures contain at least two phases) Interface – a boundary between two phases

11. Key vocabulary
Material – any type of matter – includes both substances and mixtures.
Mixing – jumbling two or more materials together. This is a physical change which involves no breaking or forming of bonds.
Combining – chemical bonding together of two or more substances in a specific ratio.

12. Mixing vs. Combining
Q: What do you get when you mix hydrogen and oxygen?
A: You get a MIXTURE of hydrogen and oxygen.

13. Mixing vs. Combining
Q: What do you get when you COMBINE hydrogen and oxygen?
A: Water!!

14. Classifying Changes… Physical Change – Same stuff, different form
Ex: cutting, folding, tearing, crushing, melting, boiling, mixing, pulverizing, etc.,
Chemical Change – At least one new substance is formed
Ex: burning, fermenting, reacting, oxidizing, rusting, etc.,

15. Classifying Properties…
DEFINE… Physical Properties Chemical Properties Intensive Properties Extensive Properties

16. Classifying Properties…
Properties may be classified as chemical or physical.
Properties may ALSO be classified as intensive or extensive.

17. Classifying Properties…
A particular property may be…
…physical AND intensive,
…physical AND extensive,
…chemical AND intensive, or
…chemical AND extensive

18. Intensive vs. Extensive PROPERTIES
Intensive Properties are NOT dependent on the amount, only on the type of material.
Ex: color, texture, conductivity, malleability, etc.,
Extensive Properties depend on the amount of the material present.
Ex: mass, volume, length, moles, etc.,

19. Intensive or Extensive?
volume
extensive
height
extensive
texture
intensive
color
intensive
density
intensive

20. Physical vs. Chemical PROPERTIES
Physical Property – any characteristic that can be observed without changing a substance into another substance.
Ex: color, mass, volume, density, conductivity, temperature, malleability, etc.,
Chemical Property – any characteristic that cannot be observed without changing a substance into another substance.
Ex: flammability, reactivity (or stability), corrosiveness, etc.,

21. Chemical or Physical? mass physical flammability chemical tarnishes
solubility
physical
density
physical

22. _ _ _ _ _ _ _ _ _ _ _

23. (*Usually in the form of HEAT in chemistry!)
What is calorimetry?
-metry means…
…measurement of
Calori- means…
…energy*.
(*Usually in the form of HEAT in chemistry!)

24. Heat is a total quantity of energy.
What is HEAT?
HEAT ≠ TEMPERATURE!!!
Heat is a total quantity of energy.
Temperature is an indicator of the AVERAGE kinetic energy of the atoms or molecules in a system.

25. So how do we “measure” HEAT?
Heat is not measured directly, it is calculated by taking into account 3 factors…
…the temperature change of a material,
…the mass of the material, and…
…the ability of the material to absorb heat (or energy).

26. So how do we “measure” HEAT?
These 3 factors are combined to form the equation; q = mcDt* where
q = heat (some sources use H instead of q)
m = mass
c = specific heat capacity (defined on next slide, some sources use s instead of c) and
Dt = change in temperature
*(H=mcDt, q=msDt, H=msDt are all the same equation)

27. Specific Heat Capacity is…
A physical constant which quantifies the ability of a substance to absorb energy.
The amount of energy needed to raise the temperature of one gram of a substance by one C°.
(ex. cH2O=4.184 J/gC°)

28. Let’s talk about “D”
Fat Albert wants to become “Fit” Albert. After dieting for a few weeks, Albert dropped from 420 lbs. to 372 lbs. What was his change in weight? How much weight did he lose?

29. Let’s talk about “D”
You check your bank account balance at the beginning of the month – you have $500. At the end of the month, you have $300. What was the change in your account? How much money did you withdraw?

30. Let’s talk about “D”
NORMALLY… Dx = final x – initial x HOWEVER, if we are calculating an amount LOST or SPENT, we switch this around to avoid a double negative. (Negative heat lost would actually mean heat gained, right?)

31. Example #1 – Calculate Heat
How much energy is needed to heat g of iron from 25.0°C to 99.8°C? (ciron= J/gC°)
Example #1 – Calculate Heat

32. Calorimetry and the Law of Heat Exchange
Review: The Law of Conservation of Energy
The Law of Heat Exchange is a specific application of the Law of Conservation of Energy;
qlost = qgained
Although the heat lost by the hot object may go several places, if the hot object is placed in water, virtually all of its heat loss is absorbed by the water.

33. If a 37. 28 g piece of metal is heated to 95
If a g piece of metal is heated to 95.0°C and then dropped into 65.0 mL of water at 26.1°C and the final temperature of the system is 26.8°C, what is the specific heat capacity of the metal?
Example #2 – Find “c”

34. Example #3 – Predict final temp.
If a g piece of aluminum is heated to 95.0°C and dropped into mL of water at 24.6°C, what will be the final temperature of the system? (CAluminum= J/gC°)
Example #3 – Predict final temp.