1. Matter --- Properties and Changes
2017 – 2018

2. Properties of Matter
Matter is anything that has mass and takes up space.
Matter with a uniform and unchanging composition is called a substance.
Examples: Air, microbes, table salt (sodium chloride), and pure water.

3. States Of Matter States of matter is the physical form of a substance.
Solid: Has its own definite shape and volume.
Examples: Wood, iron, paper, and sugar.
Liquids: Matter that flows, has constant volume, and takes the shape of its container.
Examples: water, blood, and mercury.
Gases: Matter that not only flows to conform to the shape of its container but also fills the entire volume of its container.
Vapor: is the gaseous state of a substance that normally exists as a solid or a liquid in its natural state.

4. Physical Properties of Matter
A physical property is a characteristic of matter that can be observed or measured without changing the sample’s composition.
Extensive properties: are dependent on the amount of substance present. Example: Mass, length, and volume.
Intensive properties: are independent of the amount of substance present. Example: Density.

5. Chemical Properties of Matter
The ability or inability of a substance to combine with or change into one or more other substances.

6. Changes in Matter
Physical Changes: A process that alters a substance without changing its composition. Examples: breaking, cutting, grinding, and ripping.
Phase change: is a transition of matter from one state to another. Examples: boil, freeze, condense, vaporize, or melt in chemistry generally refer to a phase change in matter.

7. Chemical Changes
Chemical change: A process that involves one or more substances changing into new substances.
Signs of a Chemical Reaction:
Heat is given off or absorbed.
Light is given off.
Gas or precipitate is formed.
Color change not due to moister loss or gained.
Odor change.
Change is not easily reversed.

8. Law of Definite Proportions
Law of Proportions states that a compound is always composed of the same elements in the same proportion by mass, no matter how large or small the sample.
Percent by mass is the ratio of the mass of each element to the total mass of the compound expressed as a percentage.
Percent by mass(%) = mass of element/mass of compound X 100

9. Law of Multiple Proportions
The law of multiple proportions states that when different compounds are formed by a combination of the same elements, different masses of one element combine with the same fixed mass of the other element in a ratio of small whole numbers.
Examples: H2O, H2O2

10. The Roots of Atomic Theory
Democritus (460 – 370 B.C.)
Matter is composed of atoms, which move through empty space.
Atoms are solid, homogeneous, indestructible, and indivisible.
Different kinds of atoms have different sizes and shapes.
Size, shape, and movement of atoms determine the properties of matter.

11. Aristotle ( B.C.)
Empty space cannot exist.
Matter is made of earth, fire, air, and water.

12. Dalton’s Atomic Theory
Matter is composed of extremely small particles called atoms.
Atoms are indivisible and indestructible.
Atoms of a given element are identical in size, mass, and chemical properties.
Atoms of a specific element are different from those of another element.
Different atoms combine in simple whole-number ratios to form compounds.
In a chemical reaction, atoms are separated, combined or rearranged.

13. Conservation of mass
The mass of the reactants equal the mass of the products in any chemical reaction.

14. The Atom
The smallest particle of an element that retains the properties of the element
Made up of protons, electrons, and neutrons.

15. J. J. Thomson Experiment: Cathode ray tube (1897)
Discovered electron!!!
Electron is negatively charged
Measured charge-to-mass ratio of electron

16. J. J. Thompson

17. Thomson’s Model: Plum Pudding

18. Robert Millikan Experiment: Oil drop experiment (1909)
Measured charge of electron
Both charge of electron and charge-to-mass ratio were used to determine the mass of an electron
Mass of electron is 1/1837 mass of hydrogen atom (essentially massless)

19. Billiard Ball Plum Pudding Planetary Model

20. Robert Millikan

21. Discovery of the Nucleus

22. Ernest Rutherford Experiment: Gold foil experiment
Discovered nucleus!!!!
All mass of an atom is in the nucleus
Nucleus is VERY massive

23. Ernest Rutherford

25. Rutherford’s model of the atom
Planetary Model

26. Billiard Ball Plum Pudding Planetary Model

27. John Dalton JJ Thompson Robert Milikan Ernest Rutherford
JJ Thompson
Robert Milikan
Ernest Rutherford

28. Brian Cox – Gold Foil http://www.youtube.com/watch?v=wzALbzTdnc8
Cathode Ray:

29. The Periodic Table Mass
Atomic mass unit (amu): One-twelfth the mass of a carbon-12 atom.
Masses of subatomic particles
Charge
Mass
Relative Mass
Relative Charge
Proton 1
1.673 X10-24 1+
Electron -
No Mass
1/1840 1-
Neutron
No Charge
1.675 X10-24

30. Atomic Number
Atomic Number: The number of protons in the atom. Because the atom is neutral in charge it is also the number of electrons in the atom.
(Average) Atomic Mass: of an element is the weighted average mass of the isotopes of that element.
Examples:

31. Mass Number
Mass number is the sum of the atomic number (or number of protons) and neutrons in the nucleus.
Mass Number = atomic number + number of neutrons

32. Isotopes
Isotopes: Atoms with the same number of protons but different numbers of neutrons.
Examples:

33. Examples: Calculating Atomic Mass Isotope Abundance for Element X
Calculate the atomic mass of element X
Isotope
Mass(amu)
Percent Abundance 6X
6.015
7.59% 7X
7.016
92.41%

34. Calculate the atomic mass of element X and identify the element from the periodic table knowing that it has the following isotopes: X (mass: , abundance: 5.9%), 56 X (mass: , abundance: 91.72%), 57 X (mass: , abundance: 2.1%), and 58 X (mass: , abundance: 0.28%)

35. Notation Hyphen Notation (name): Name-mass number Examples:
Nuclear Notation (Symbol)

36. Assignment Page 105: 1-6 Page 114: 7-11 Page 116: 12-14