Chapter 1 Matter & Measurement
1.1 Chemistry the Central Science
What is chemistry?
Chemistry: the study of nature, properties & transformations of matter.
Matter: Anything that has mass and occupies space. (The stuff around us)
Chemistry is often referred to as the “Central Science”.
Multiple sub-disciplines
Organic – organic based compounds
Inorganic – All other elements
Biochemistry – Study of biological chemicals
Analytical – Methods of Analysis
Physical – Theory and Concepts
Petrochemical – Chemicals from Coal, tar, oil, etc.
Chapter (1 Part 1) Page 1 of 8
Chemical and Physical Properties
Physical Property
A characteristic that can be observed without changing the composition of the substance. (e.g., size, color,
weight)
Qualitative
Quantitative
Color
Melting point
Odor
Boiling point
Taste
Weight
Chemical Property
Describes how a substance reacts with other substances.
These result in a change in the composition of a material as a result of a chemical reaction.
Problem: Are the following examples of chemical or physical properties?
type?
Lead is denser than aluminum
_____________
oxygen gas supports combustion
_____________
Water boils below 100 degrees at altitudes
_____________
Physical and Chemical Changes
Physical Changes
DO NOT alter the chemical makeup of a substance.
e.g., Phase changes are examples of physical changes.
Chemical Changes
DO alter the chemical makeup.
They involve a chemical reaction
e.g., a nail rusting or burning the fuel in your car.
Problem: Are the following examples of chemical or physical changes?
Type of Change?
Milk turning sour
making wine from grapes
water freezing
plants undergoing photosynthesis
helium leaking out of a balloon
_________
_________
_________
_________
_________
Chapter (1 Part 1) Page 2 of 8
1.2 States of Matter
States of Matter
−
Matter exists in three
phases;
Phase depends on
temperature and pressure
Changes of State
_________ to go from a liquid to a solid
_________ to go from a solid to a liquid
_________ to go from a liquid to a gas
_________ to go from a gas to a liquid
_________ to go directly from a solid to a gas (without first becoming a liquid)
_________ to go from a gas directly to a solid
Problem: Acetic acid, (which gives the sour taste to vinegar), has a melting point of 16.7 °C and a boiling point of
118 °C. Predict the physical state of acetic acid when the ambient temperature is 10 °C.
.
solid
10 °C
m.p.
16.7 °C
liquid
b.p.
118 °C
(End of Day 1)
Chapter (1 Part 1) Page 3 of 8
Gas
1.3 Classification of Matter
Example of a chemical process that would break up a compound into its elements:
Emphasize reactants, products and arrow.
Problem: Classify each of the following as a mixture or a pure substance.
If a mixture – decide homogeneous or heterogeneous.
If a pure substance – decide compound or element.
a)
Vanilla ice cream – Mixture: Homogenous
b) Sugar – Pure Substance: Compound
Problem: how many elements of each type are in one formula unit of Al2(S2O3)3?
Chapter (1 Part 1) Page 4 of 8
1.5 Elements and the Periodic Table
Periodic Table
•
Developed by Demitri Mendeleev - Hand out Periodic Tables
•
Arranged so that elements with similar properties are grouped together. (see next section)
•
Metals (94 of 118): (to the left of the stair-step line)
•
Semimetals or Metalloids have properties between that of a metal and a nonmetal.
semimetals: Textbooks differ, semimetals are Si, Ge, As, Sb, Te,
(Sometimes boron (B), astatine(At) and/or polonium (Po).
We will consider all elements touching the line (except Al) as a semimetal.
•
Nonmetals: (to the right of the stair-step line)
(Metals to the left of the line, nonmetals to the right)
Chapter (1 Part 1) Page 5 of 8
Elements to Know
Aluminum
Al
13
Manganese
Mn
25
Antimony
Sb
51
Mercury
Hg
80
Argon
Ar
18
Molybdenum
Mo
42
Arsenic
As
33
Neon
Ne
10
Barium
Ba
56
Nickel
Ni
28
Beryllium
Be
4
Nitrogen
N
7
Bismuth
Bi
83
Oxygen
O
8
Boron
B
5
Phosphorus
P
15
Bromine
Br
35
Plutonium
Pu
94
Cadmium
Cd
48
Potassium
K
19
Calcium
Ca
20
Radium
Ra
88
Carbon
C
6
Radon
Rn
86
Cesium
Cs
55
Rubidium
Rb
37
Chlorine
Cl
17
Selenium,
Se
34
Chromium
Cr
24
Silicon
Si
14
Cobalt
Co
27
Silver
Ag
47
Copper
Cu
29
Sodium
Na
11
Fluorine
F
9
Strontium
Sr
38
Gold
Au
87
Sulfur
S
16
Helium
He
2
Thallium
Tl
81
Hydrogen
H
1
Tin
Sn
50
Iodine
I
53
Titanium
Ti
22
Iron
Fe
26
Tungsten
W
74
Krypton
Kr
36
Uranium
U
92
Lead
Pb
82
Vanadium
V
23
Lithium
Li
3
Xenon
Xe
54
Magnesium
Mg
12
Zinc
Zn
30
Chapter (1 Part 1) Page 6 of 8
Metallic Character
Metal
State
Appearance
Pliability
Conductivity
Density
Melting pt.
Reactivity
Solid (liq Hg)
Shiny when cut
Malleable (bendable)
ductile (draws into wire)
Good conductor
Usually high
Usually high
With nonmetals
Nonmetal
Solid, gas(liq Br2)
Dull
Brittle
Poor cond
Usually low
Usually low
With metals or nonmetals
1.6 Chemical Reactions:
An example of Chemical Change.
Reactions
The process of ethanol burning in oxygen is an example of a chemical reaction. We can write a chemical
equation to show what is happening in the reaction:
CH3CH2OH + 3O2 2 CO2 + 3 H2O
Reactants are elements and compounds on the left of arrow.
Products are elements and compounds on the right of arrow.
Evidence of Chemical Reaction:
1.
Precipitate form
2.
Gas formation
3.
Color formation
4.
Heat
Chapter (1 Part 1) Page 7 of 8
Matter
Mixtures
homogeneous
Pure Substances
heterogenous
elements
monotomic
metalic properties
metals
semimetals
same
atoms
molecules
diatomics and higher
nonmetals
Chapter (1 Part 1) Page 8 of 8
different
atoms
covalent
compounds
ionic