the modern theory of atomic structure - d...
TRANSCRIPT
The Modern Theory of
Atomic Structure
Atoms can be broken down into smaller
particles. This was first done with a
Crooke’s Tube.
Particles which make up the atom are
called subatomic particles.
Protons
Protons
Positively
charged
particles in
the nucleus
Protons
Positively
charged
particles in
the nucleus
Neutrons
Protons
Positively
charged
particles in
the nucleus
Neutrons - Neutral
particles in the nucleus
Protons
Positively
charged
particles in
the nucleus
Neutrons - Neutral
particles in the nucleus
Electrons
Protons
Positively
charged
particles in
the nucleus
Neutrons - Neutral
particles in the nucleus
Electrons –Small negative
particles outside
the nucleus
Electron
Neutron
Proton
LocationChargeMass
(P = 1)
Particle
Electron
Neutron
nucleus+1Proton
LocationChargeMass
(P = 1)
Particle
Electron
nucleus01Neutron
nucleus+1Proton
LocationChargeMass
(P = 1)
Particle
outside-1
1837
Electron
nucleus01Neutron
nucleus+1Proton
LocationChargeMass
(P = 1)
Particle
Atomic Number = The # of Protons in
the Nucleus
Found on top of element symbol
Do “Instant Practice” on top of page 170
36Krypton
Cobalt
Carbon
4Beryllium
1Hydrogen
Number of
Protons
Atomic
Number
SymbolElement
Do “Instant Practice” on top of page 170
36KrKrypton
CoCobalt
CCarbon
4BeBeryllium
1HHydrogen
Number of
Protons
Atomic
Number
SymbolElement
Do “Instant Practice” on top of page 170
36KrKrypton
27CoCobalt
6CCarbon
4BeBeryllium
1HHydrogen
Number of
Protons
Atomic
Number
SymbolElement
Do “Instant Practice” on top of page 170
3636KrKrypton
2727CoCobalt
66CCarbon
44BeBeryllium
11HHydrogen
Number of
Protons
Atomic
Number
SymbolElement
Hydrogen
Hydrogen
Hydrogen Hydrogen
Hydrogen Hydrogen
Hydrogen Hydrogen Hydrogen
Hydrogen-1 Hydrogen Hydrogen
Hydrogen-1 Hydrogen-2 Hydrogen
Hydrogen-1 Hydrogen-2 Hydrogen-3
Hydrogen-1 Hydrogen-2 Hydrogen-3
Isotopes of Hydrogen
Isotopes are:
Different forms of the same element
with the SAME # of Protons but with
DIFFERENT #’s of Neutrons
Hydrogen-1 Hydrogen-2 Hydrogen-3
Isotopes of Hydrogen
1H
Hydrogen-1 Hydrogen-2 Hydrogen-3
Isotopes of Hydrogen
1H 2H
Hydrogen-1 Hydrogen-2 Hydrogen-3
Isotopes of Hydrogen
1H 2H3H
Mass Number = Total Protons + Neutrons
in an isotope of an element
3HMass Number
P + N
Mass Number = Total Protons + Neutrons
in an isotope of an element
3HMass Number
P + N
1 P + 2 N’s
Mass Number = Total Protons + Neutrons
in an isotope of an element
3HMass Number
P + N
1 P + 2 N’s
Also called “Hydrogen – 3”
3H
Called the “Nuclear Notation”
To find P’s and N’s from Nuclear Notation
41Ca
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
So it has 20 Protons
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
So it has 20 Protons
To find # of
Neutrons, put
Atomic Number
Here:
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
So it has 20 Protons
To find # of
Neutrons, put
Atomic Number
Here: 20
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
So it has 20 Protons
To find # of
Neutrons, put
Atomic Number
Here: 20
Mass # = P + N
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
So it has 20 Protons
To find # of
Neutrons, put
Atomic Number
Here: 20
Mass # = P + N
Subtract to get #
of Neutrons
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
So it has 20 Protons
To find # of
Neutrons, put
Atomic Number
Here: 20
Mass # = P + N
Subtract to get #
of Neutrons
21
To find P’s and N’s from Nuclear Notation
41CaCalcium’s atomic
Number = 20
So it has 20 Protons
To find # of
Neutrons, put
Atomic Number
Here: 20
Mass # = P + N
Subtract to get #
of Neutrons
21
So it has 21 Neutrons
Find the # of Protons and # of Neutrons in
Each of the Following Isotopes:
12C
237Np
56Mn
54Fe
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Find the # of Protons and # of Neutrons in
Each of the Following Isotopes:
12C
237Np
56Mn
5454Fe
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Find the # of Protons and # of Neutrons in
Each of the Following Isotopes:
12C
237Np
56Mn
54 – 26 =
2826265454Fe
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Find the # of Protons and # of Neutrons in
Each of the Following Isotopes:
12C
237Np
3125255656Mn
54 – 26 =
2826265454Fe
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Find the # of Protons and # of Neutrons in
Each of the Following Isotopes:
12C
1449393237237Np
3125255656Mn
54 – 26 =
2826265454Fe
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Find the # of Protons and # of Neutrons in
Each of the Following Isotopes:
6661212C
1449393237237Np
3125255656Mn
54 – 26 =
2826265454Fe
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
7855
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
785555
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
78555555 + 78 =
133
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017
54130
12882
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017
54130
1288282
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017
54130
1288282210
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017
54130
1288282210210Pb
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017
5454130
1288282210210Pb
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017
130 – 54 =
765454130
1288282210210Pb
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017
130 – 54 =
765454130130Xe
1288282210210Pb
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Now try the other way!
2017173737Cl
130 – 54 =
765454130130Xe
1288282210210Pb
78555555 + 78 =
133133Cs
# of
Neutrons
# of
Protons
Atomic #Mass #Isotope
Radioactive Isotopes
-Isotopes that have unstable nuclei
-They “fall apart” giving off radiation
Cobalt – 60 or 60Co
-Is used to kill cancer cells in radiation
therapy
Uranium-235
or 235U is
used to make
atomic
bombs!
Radiation from
atomic bombs can
cause severe
radiation burns
to the skin!
Hydrogen-2 or 2H is called deuterium.
Deuterium oxide 2H2O is also called
“Heavy Water”
It is used in Canadian (CANDU) nuclear
power plants.
Lithium on Earth is about 7% 6Li and 93% 7Li.
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
=
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
= 7 x 6 = 42
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
= 7 x 6 = 42
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Total Mass of 7Li
=
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
= 7 x 6 = 42
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Total Mass of 7Li
= 93 x 7 = 651
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
= 7 x 6 = 42
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Total Mass of 7Li
= 93 x 7 = 651
Total Mass of 100
Lithium Atoms
=
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
= 7 x 6 = 42
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Total Mass of 7Li
= 93 x 7 = 651
Total Mass of 100
Lithium Atoms
= 42 + 651 = 693
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
= 7 x 6 = 42
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Total Mass of 7Li
= 93 x 7 = 651
Total Mass of 100
Lithium Atoms
= 42 + 651 = 693
Average Mass of 1 Li
Atom = 693/100 =
Lithium on Earth is about 7% 6Li and 93% 7Li.
Total Mass of 6Li
= 7 x 6 = 42
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
7 7 7 7 6 7 7 7 7 7
7 7 7 7 7 7 7 7 7 7
7 7 7 7 7 7 7 7 6 7
7 7 6 7 7 7 7 7 7 7
7 7 7 7 7 7 6 7 7 7
Total Mass of 7Li
= 93 x 7 = 651
Total Mass of 100
Lithium Atoms
= 42 + 651 = 693
Average Mass of 1 Li
Atom = 693/100 = 6.93
The “weighted average” mass of isotopes of
an element is called it’s Atomic Mass
The “weighted average” mass of isotopes of
an element is called it’s Atomic Mass
It is shown underneath the symbol on the
Periodic Table
Bh
Se
Ag
Atomic Mass
Number of
Protons
Atomic
NumberElement
Bh
Se
107.94747Ag
Atomic Mass
Number of
Protons
Atomic
NumberElement
Bh
79.03434Se
107.94747Ag
Atomic Mass
Number of
Protons
Atomic
NumberElement
262107107Bh
79.03434Se
107.94747Ag
Atomic Mass
Number of
Protons
Atomic
NumberElement
262107107Bh
79.03434Se
107.94747Ag
Atomic Mass
Number of
Protons
Atomic
NumberElement
Mass of most stable
isotope
In a Neutral Atom of an Element:
The # of Electrons(-) = The # of Protons(+)
In a Neutral Atom of an Element:
The # of Electrons(-) = The # of Protons(+)
Neutral Carbon has ____ Protons
In a Neutral Atom of an Element:
The # of Electrons(-) = The # of Protons(+)
Neutral Carbon has 6 Protons
Neutral Carbon has __ Electrons
In a Neutral Atom of an Element:
The # of Electrons(-) = The # of Protons(+)
Neutral Carbon has 6 Protons
Neutral Carbon has 6 Electrons
When white light is shone through a
prism, it is separated into different
colours.
The Pattern of Colours is called a
SPECTRUM
If a single element is subjected to a high
voltage, it has a spectrum too, but it is
different!
If a single element is subjected to a high
voltage, it has a spectrum too, but it is
different!
The spectrum of Hydrogen only has a
few “lines”
Niels Bohr
A Danish
Physicist
Bohr said the atom has different “Energy
Levels” or “Orbits” or “Shells” which the
electrons could inhabit.
When energy is added to an atom, the
electron “jumps” to a higher orbit (the atom
is then in an “excited state”)
When electrons jump
from higher orbits
back to lower orbits,
they “give off” energy
in the form of light.
Different “jumps”
give different colours.
Since atoms of
different
elements have
different
electron
arrangements,
each element
has its own
unique
spectrum!
Spectra can be used to “identify” an
unknown element – like a fingerprint!
Bohr’s Orbits
882
Maximum
# of
Electrons
Third
Orbit
Second
Orbit
First
Orbit
Bohr Models:
He
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Bohr Models:
00222He
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Bohr Models:
00222He
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
He
Bohr Models:
C
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Bohr Models:
04266C
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Bohr Models:
04266C
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
C
Bohr Models:
04266C
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
C
Bohr Models:
N
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Bohr Models:
05277N
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
NN
Bohr Models:
05277N
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
NN
Bohr Models:
Cl
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Bohr Models:
7821717Cl
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Cl
Bohr Models:
7821717Cl
Electrons
in Third
Orbit
Electrons
in Second
Orbit
Electrons
in First
OrbitTotal # of
Electrons
Atomic
NumberElement
Cl