Transcript Nanochemistry FNI 1E Chemistry Review of Chemistry States of Matter  Atoms, Molecules and Ions  Subatomic particles  Periodic Table  Covalent and ionic bonding 

Nanochemistry
FNI 1E Chemistry
1
Review of Chemistry
States of Matter
 Atoms, Molecules and Ions
 Subatomic particles
 Periodic Table
 Covalent and ionic bonding
 Chemical reactions
 Inter-molecular forces

FNI 1E Chemistry
2
States of Matter
Solid
Keeps shape
Keeps
volume
Salt, gold,
copper
Liquid
Takes shape
of container
Keeps
volume
Water,
alcohol, oil
Gas
Takes shape
of container
Takes volume Air, argon,
of container
helium,
methane
Plasma – like
a gas of
charged
particles.
Takes shape
of container
Takes volume Stars, nebula,
of container
lightning,
plasma
reactors
FNI 1E Chemistry
3
Matter

Solution: A uniform mixture of two substances
such that molecules are separate from each
other and move around randomly. Usually these
are liquids. Solutions are usually transparent.

Colloids: A mixture of much larger particles
ranging from 20 nm to 100 μm. Milk and paint
are colloids.

Grains: Some materials are made up of many
small crystals called grains. A grain is an
individual crystal of such a solid. Different grains
may have the crystal lattice oriented in different
directions.
4
FNI 1E Chemistry
Grain Structure in Steel
FNI 1E Chemistry
5
Elements, Atoms and Molecules

Atoms: All matter is made up of tiny particles called atoms.

Molecules: Sometimes two or more atoms are found bound together
to form molecules.

The atoms can be categorized into about 115 different types based
on the charge of the nucleus.

Elements are made up of only one type of atom.

The element carbon takes the form of graphite, diamond and
buckminsterfullerene as well as others.

It is only possible to change one type of atom into another through
nuclear processes such as take place in a nuclear power plant, the
sun, atomic bombs or particle accelerators.

The elements do not change in ordinary chemical reactions.
FNI 1E Chemistry
6
The Periodic Table
1
H
2
He
3
Li
4
Be
5
B
6
C
7
N
8
O
9
F
10
Ne
11
Na
12
Mg
13
Al
14
Si
15
P
16
S
17
Cl
18
Ar
19
K
20
Ca
21
Sc
22
Ti
23
V
24
Cr
25
Mn
26
Fe
27
Co
28
Ni
29
Cu
30
Zn
31
Ga
32
Ge
33
As
34
Se
35
Br
36
Kr
37
Rb
38
Sr
39
Y
40
Zr
41
Nb
42
Mo
43
Tc
44
Ru
45
Rh
46
Pd
47
Ag
48
Cd
49
In
50
Sn
51
Sb
52
Te
53
I
54
Xe
55
Cs
56
Ba
57
La
72
Hf
73
Ta
74
W
75
Re
76
Os
77
Ir
78
Pt
79
Au
80
Hg
81
Tl
82
Pb
83
Bi
84
Po
85
At
86
Rn
87
Fr
88
Ra
89
Ac
104
Rf
105
Db
106
Sg
107
Bh
108
Hs
109
Mt
110
Ds
111
112
113
114
115
116
117
118
58
Ce
59
Pr
60
Nd
61
Pm
62
Sm
63
Eu
64
Gd
65
Tb
66
Dy
67
Ho
68
Er
69
Tm
70
Yb
71
Lu
90
Th
91
Pa
92
U
93
Np
94
95
96
97
1E Chemistry
Pu FNIAm
Cm Bk
98
Cf
99
Es
100
Fm
101
Md
102
No
103
Lr
7
Subatomic Particles
Most of matter is made of three subatomic particles:
Particle
Symbol
Relative Relative Location
Charge Mass
Electron e-
-1
1
p+
+1
1836
Electron
Cloud
Nucleus
0
1839
Nucleus
Proton
Neutron n0
FNI 1E Chemistry
8
Ions

Usually atoms have the same number of electrons as
protons so the charges cancel each other out.

Sometimes an atom can have more or fewer electrons
than protons resulting in a net positive or negative
charge. When this happens it is called an ion.

Example: Na loses an electron to form Na+

Chlorine can gain an electron to from Cl-

We can tell what type of charge an ion is expected to
have by looking at where it is in the periodic table.
FNI 1E Chemistry
9
Isotopes
Atoms with the same number of protons
but different numbers of neutrons
 Deuterium, tritium, Carbon 12, U235
 Some isotopes are radioactive while
others are stable

FNI 1E Chemistry
10
The Atom Game
FNI 1E Chemistry
11
Electron Orbitals
1s
2s
http://www.shef.ac.uk/chemistry/orbitron/
2p
FNI 1E Chemistry
12
Chemical Bonding
Covalent bonds
 Ionic bonds
 Metal bonding

FNI 1E Chemistry
13
Covalent bonds

Covalent bonding is when electrons are shared between
to atoms or more.

The number of covalent bonds an atom is likely to form
is determined by its place in the periodic table and the
number of valence electrons it has.

An atom will share electrons with another atom so that it
results in them both having a full valence shell. Usually
this will be 8 electrons.
FNI 1E Chemistry
14
Ionic bonds

When a metal and a non-metal form bonds they
are typically ionic bonds where electrons are
transferred from the metal to the non-metal.

Some metals will lose enough electrons to
achieve a complete valence shell.

Non-metals will usually gain enough electrons to
achieve a complete valence shell.

Many metals are able to form ions with more
than one charge.
FNI 1E Chemistry
15
Metal bonding

In metals the atoms are held together by metal bonding.
Electrons can easily transfer from one atom to the next.
This suggests a model of positive ions in a sea of
electrons. Metals can conduct electricity because
electrons flow easily in any direction.
FNI 1E Chemistry
16
Covalent and Ionic Bonding
Atom
# of Covalent Bonds
Typical charge for an
Ion
H
1
+1
C
4
O
2
N
3
F, Cl, Br, I
1
-1
S
2
-2
Si
4
-2
Li, Na, K
+1
Be, Mg, Ca, Sr, Ba
+2
FNI 1E Chemistry
17
Electronegativity and Polar
Molecules

Electronegativity
 This
is the tendency for a type of atom to
attract electron density.

Polar Molecules
 If
the electron density is not distributed evenly
around a molecule then they are polar.

http://www.nyu.edu/pages/mathmol/library/
FNI 1E Chemistry
18
Intermolecular Bonding
Bonding between molecules
van der Waals forces

Hydrogen bonding
 This
relatively strong type of inter-molecular bonding
which typically occurs between a hydrogen atom of
one molecule and an electron pair or electronegative
atom of another molecule.
 Multiple hydrogen bonds hold the DNA double helix
together.


Dipole interaction
London forces
 These
are induced forces caused by a temporary
rearrangement of the electron clouds when molecules
bump together.
FNI 1E Chemistry
19
Hydrogen Bonding
+
-
H
O
H
FNI 1E Chemistry
+
-
20
Hydrogen Bonding
H
O
H
H
O
H
FNI 1E Chemistry
21
Dipole Interaction

http://www.chemguide.co.uk/atoms/bonding/vdw.html

The partial positive and negative ends of
the molecules hold the molecules together.
FNI 1E Chemistry
22
London Forces
London forces are induced dipoles caused by
temporary rearrangement of the electron cloud.
Two hexane
molecules
approach.
The hexane
molecules bump
into each other.
The electron clouds
rearrange to form a
temporary dipole.
-
-
-
+
- + +
FNI 1E Chemistry
+
+
+
23
Polymers


Polymers are large chainlike molecules that are
built from smaller molecules called monomers.
For example polyethylene is formed from
ethylene:
nCH2=CH2
(
H
H
C
C
H
H
)
n

Proteins are natural polymers.

http://www.pslc.ws/macrog.htm
FNI 1E Chemistry
24
Chemical Reactions
Involve the making or breaking of chemical
bonds.
 Chemical reactions result in making a new
substance with different properties from
the original substance.

FNI 1E Chemistry
25
Structure of
Materials
Grains
Unit Cell
Crystals
Atom
FNI 1E Chemistry
Crystal
Electron orbitals
26
Biological Organization
Tissue
Membranes
Cells
Proteins
FNI 1E Chemistry
Organelles
Nucleic Acids
27
Mind Map
FNI 1E Chemistry
28
Review of Chemistry
States of Matter
 Atoms, Molecules and Ions
 Subatomic particles
 Periodic Table
 Covalent and ionic bonding
 Chemical reactions
 Intra-molecular forces
 Polymers

FNI 1E Chemistry
29