Ch.2 Science Notes
(part1)
M atter and Change
Section 2-1: Properties of Matter
I.
Describing Matter i.
A physical property is a quality or condition of a substance that can be measured without changing the composition (make-up) of the substance. ii.
There are two types of physical properties:
1.
Extensive vs. Intensive Properties
2.
An Extensive Property is a property that depends on the amount of matter that there is. a.
Two examples of extensive properties are the mass and volume of a diamond. i.
The reasoning is, if you cut a diamond into two pieces each of those pieces will have less mass and volume compared to the initial first piece. Thus, mass and volume are extensive properties affected by the amount of material present.
3.
An Intensive Property depends on the type of matter in a sample,
not the amount of matter. Some intensive properties include temperature, color, and hardness of an object. a.
Thus, no matter how small a diamond is cut, it maintains its same hardness.
4.
Therefore, amount of matter affects extensive properties but does not affect intensive properties . iii.
Matter that has a uniform and definite composition is called a substance .
1.
*Every sample of a given substance has identical intensive properties because they share the same composition.

II.
Matter is something that has mass and takes up space (volume). Matter makes up less than 5% of the universe. The rest consists of Dark Matter and Dark Energy.
I.
Matter exists in 4 states: i.
Solid ii.
Liquid iii.
Gas iv.
Plasma
Examples of the 4 states of matter
An ice cube is an example of a solid
Water is an example of a liquid

A cloud is an example of matter in the gas state
The Earth atmosphere is another example of matter in the gas state

Lightning is an example of matter in the plasma state
The Sun is another example of matter in the plasma state
Plasma is the most abundant form of matter in the Universe, because most stars are in a plasma state

III.
Phases of Matter
I.
A Solid is a form of matter that has a definite shape and volume.
II.
A Liquid is a form of matter that has an indefinite shape, flows, yet has a fixed volume.
III.
Gas vs. vapor i.
A gas is a form of matter that takes both the shape and volume of its container. ii.
Although gas and vapor are sometimes used interchangeably, the term gas is used for substances that exist in the gaseous state in room temperature and the term vapor describes the gaseous state of a substance that is generally a liquid or a solid in room temperature.
IV.
Plasma consists is ionized gas consisting of positive ions and free electrons. Like gas, plasma has no definite shape or volume; unlike gas however, it can form structures such as beams of energy.
A plasma globe, illustrating some of the more complex phenomena of plasma, namely filamentation

IV.
Physical Changes
I.
During a physical change , some properties of a material change, but the composition of the material does not change. i.
Physical Change can be classified as reversible or irreversible.
1.
A reversible physical change includes melting or changing the phase of matter.
2.
An irreversible physical change includes: Cutting hair, filing nails, and cracking an egg.
Section 2-2:
I.
A Mixture – a physical blend of two or more substances. Mixtures are only physically combined, there is no chemical combination. i.
There are two types of mixtures: Heterogeneous and Homogeneous

ii.
Heterogeneous mixture – components not mixed evenly; each component retains its own properties.
1.
Examples of heterogeneous mixtures:

b.
Homogeneous mixture – components that evenly mix; can’t see each component; also called solutions . i.
Examples of homogeneous mixtures

II.
Components of a mixture can be separated by physical means a.
Differences in physical properties can be used to separate mixtures i.
The Separation techniques:
1.
Filtration
2.
Distillation
3.
Magnetic Attraction
4.
Evaporation
Can you name the separation technique shown above?

What is the separation technique above?
Name the separation technique below:

* Categorize the following mixtures as homogenous or heterogeneous?

Glass of “salt” water

Ch.2 Science Notes
(part 2)
Section 2-3: Elements and Compounds
I.
Matter is made up of tiny particles called atoms . An atom is a neutral and stable particle made up of three basic subatomic particles:
A.
Protons – particles that have a positive electrical charge.
B.
Neutrons – particles that have a neutral electrical charge.
C.
Electrons – particles that have a negative electrical charge.
II.
Protons and neutrons are located in the nucleus of an atom. Electrons orbit the nucleus of an atom somewhat
similar to the way planets orbit around the Sun.
An Atom

Image #2 model of an atom
A.
Elements are substances that contain only one type of atom.
B.
Atomic Number – the number of protons in an atom’s nucleus a.
All atoms of the same kind have the same number of protons and therefore have the same atomic number.

b.
The atomic number also equals the number of electrons orbiting the nucleus in the atom’s electron cloud. i.
This is because the # of electrons and protons is equal.
C.
Mass Number – is the number of protons plus neutrons (combined), both of which are found in an atom’s nucleus. Protons + neutrons = mass number. a.
Atomic mass means the same as mass
number.
D.
Isotopes – are atoms of the same element that differ in the amount of neutrons in the nucleus.
______________________________________________________________________________

The Periodic Table of Elements
(TB pages 168-169)
Periodic Table Activity (*Use TB p. 168-169 for reference)
1) Color- coordinate element boxes by outlining each box in the following way:
A) Noble Gases (violet)
B) Nonmetals (Light-blue)
C) Metalloids (Green
2) Then use zoom to write over the element abbreviations in:
A) Dark Blue (Liquid)
B) Red (Gas)
C) Orange (Not found in nature)
D) and leave solids in black

III.
- are substances that contain only one type of atom. An element is the simplest form of matter that has a unique set of properties.
Lithium (Li 3)
Magnesium (Mg 12)

Silicon (Si 14)
Titanium (Ti 22) http://www.periodictable.com/Samples/022.18/index.pair.s10.html

Chromium (Cr 24)
Zinc (Zn 30)
Small nuggets of pure (elemental) Zinc
*See Lab samples

Germanium (Ge 32)
Niobium (Nb 41)

Palladium (Pd 46)
Silver (Ag 47)
A necklace made out of silver

Iodine (I - 53)

Xenon (Xe 54)
Osmium (Os 76)

Gold (Au 79)
Mercury (Hg 80)
Sample of Mercury

Radium (Ra 88) – (radioactive)
Radium was widely used in self-luminous clocks and watch hands until a significant amount of clock factory workers began to die from radiation poisoning. This radium-powered clock is radioactive , and will continue to be for thousands of years.

Uranium (U 92) – ( radioactive )
Uranium pic # 2
Sample of “enriched” uranium

Plutonium (Pu 94) http://www.periodictable.com/Samples/094.x1/index.pair.s9.html
instead of physically

For example:
This is a sample of the element sodium (Na 11). Sodium is a metal made of sodium atoms only, that’s why it’s an element.
This is a sample of the element chlorine (Cl 17). Chlorine is made of chlorine atoms only. This is why it’s an element.
Chlorine is also a gas

Sodium + Chlorine + 1 drop H
2
0 (catalyst)
=> sodium chloride
(table salt)

http://www.youtube.com/watch?v=Mx5JJWI2aaw&feature=player_embedded http://www.youtube.com/watch?v=Ftw7a5ccubs&NR=1 http://www.youtube.com/watch?v=gpQCgCHc0Nw&NR=1