chapter 2 notes for chemistry

1. Chapter 2
Matter and Change
Section 2.1
Properties of Matter

2. Matter has extensive and intensive properties.
Extensive property
is a property that depends on the amount of matter in a
sample.
e.g. mass and volume
Mass is a measure of the amount of matter the object
contains.
Volume is a measure of the space occupied by the object.
Intensive property
is a property that depends on the type of matter in a
sample, not the amount of matter. e.g. hardness,
temperature, pressure, density, & solubility.
Matter that has a uniform and definite composition is called
a substance.

3. Physical Property
e.g. malleability, color, hardness and conductivity.
is a quality or condition of a substance that can be observed
or measured without changing the substance’s composition.
Every sample of a given substance has identical intensive
properties because every sample has the same composition.
States of Matter
Particles are packed
closely together
Particles are packed
closely together but
they are free to flow
past one another
Particles are
relatively far apart
and can move freely
Solid Liquid Gas
Definite shape Indefinite shapeIndefinite shape
Definite volume Definite volume Indefinite volume
Not easily compressed Easily compressedNot easily compressed

4. e.g. boiling, evaporation, freezing, melting, and condensing.
These characteristics are said to be reversible physical
changes because a substance can be reformed again to its
original shape.
While cutting, breaking, splitting, crushing, and grinding are
irreversible physical changes.
If the appearance of the matter changes without changing
its composition, it is called physical change.
Vapor
is a word that describes the gaseous state of a substance
that is generally a liquid or solid at room temperature.
e.g. water vapor

5. Phase Changes
Solid Liquid Gas
Melting Vaporization
CondensationFreezing

6. Liquid
Sublimation
Melting Vaporization
Deposition
Condensation
Solid
Freezing
Gas
Require energy
Release energy

7. Vaporization is a transitional phase of an element or
compound from a liquid phase to a gas phase.
Vaporization has two types:
Boiling, wherein the transition from liquid phase to gas
phase takes place at or above the boiling temperature, and
it occurs below the surface.
Evaporation, wherein the transition from liquid phase to gas
phase takes place below the boiling temperature at a given
pressure, and it occurs on the surface.

8. Section 2.2
Mixtures

9. What is a Mixture ??
is a physical blend of two or more components, e.g. air,
juice, sea water, milk, sand and water…etc.
Homogeneous mixture
is a mixture in which the composition is uniform throughout.
Heterogeneous mixture
is a mixture in which the composition is not uniform
throughout.
e.g. sand with water, oil and water.
e.g. table salt and water, milk, coke.
These mixtures have another name which is, Solutions
A mixture with more than one phase.
A mixture consists of one phase.

10. How can we separate mixtures??
The best way for separation, solid from the liquid in
heterogeneous mixtures is filtration.
But if we have liquid with a solid dissolves in, like salt and
water (homogeneous mixture), we have to use a process
called, distillation.

11. Go to page : 47
Classwork
Page: 47, # 14

12. Section 2.3
Elements and Compounds

13. Element
is the simplest form of matter that has unique properties.
Compound
e.g. sodium (Na), hydrogen (H)
is a substance that contains two or more elements chemically
combined together.
Compounds can be broken into simpler substances but
elements cannot.
If the composition of a matter changed into a new matter
different than the original one, it is called chemical change.
e.g. sodium chloride (NaCl)

14. Classwork:
Page: 52, # 24, 25, & 26

15. Section 2.4
Chemical Reactions

16. Chemical property
is the ability of a substance to undergo a specific chemical
change.
During a chemical change, the composition of matter always
changes.
iron + sulfur iron sulfide
reactant product
a substance at the
start of the reaction
a substance produced
in the reaction

17. During any chemical reaction, the mass of the products is
always equal to the mass of the reactants
The Law of Conservation of Mass
states that in any physical change or chemical reaction,
mass is conserved. Mass is neither created nor destroyed.
e.g. If 10 grams of carbon reacts with 5 grams of oxygen
gas, 15 grams of carbon oxide is produced.

18. How can you tell whether a chemical change has taken place?
There are four possible clues to chemical change:
o a transfer of energy
o a change in color
o producing a gas
o forming a precipitate
a solid that forms and
settles out of a liquid
mixture.

19. Classwork:
Page: 55, # 31, 32, & 34