NOTES Out 1 & 2 Atom Structure.doc

ITP --- Unit 6 - Atomic Structure and Nuclear Energy

I. Outcome 1 & 2 – Subatomic Particles and the PTE.

A) SUBATOMIC – Anything smaller than an atom. The particles that make up an atom.

1) Nucleus – Dense center of the atom. Contains protons and neutrons.

-- Nucleon – particles that make up the nucleus…. Include protons and neutrons. 2) Protons – Nucleon with a positive charge. Found in nucleus.

= 1 atomic mass unit (AMU)

3) Neutrons - Nucleon with no charge. Found in nucleus.

= 1 atomic mass unit (AMU), but slightly larger than a proton. -- Responsible for binding protons together in the nucleus.

4) Electrons - Subatomic particle with a negative charge. Found orbiting outside the nucleus.

a) Electron Cloud – Area surrounding the nucleus where the electrons are likely to be found.

+ Includes all energy levels.

b) Energy levels – Paths within the electron cloud where the electrons orbit the nucleus.

+ Electrons fill energy levels from the inside out with this pattern:

Energy level Maximum electrons it can take 1st _{energy level 2}

2nd _{energy level 8}

3rd _{energy level 8}

4th _{energy level 18}

5th _{energy level 18}

6th _{& 7}th _{levels 32 each}

c) Valence Electrons – Electrons in the last energy level. Electrons that are responsible for most chemical reactions.

B) SIMPLE ATOMIC MODEL

++ All atoms of elements represented on the PTE are electrically neutral = no charge (+ or -).

++ To make the atoms neutral the protons (+) must equal the electrons(-).

D) ATOMIC NUMBER & ATOMIC MASS

1) Atomic Number – Number of protons in the nucleus of an atom.

2) Atomic Mass – Number of protons and neutrons in the nucleus of an atom. -- On the periodic table the atomic mass is given as the average of the atomic

masses of all of the isotopes of that element.

E) COUNTING PROTONS, NEUTRON & ELECTRONS. 1) Number of Protons = Atomic Number

2) Number of Electrons = Number of protons (atomic number) 3) Number of Neutrons = Atomic Mass – (subtract) Atomic Number

In other words: Atomic Mass (protons and neutrons) - Atomic Number (protons)

Ex: # of neutrons in Carbon?

Atomic mass of 12 – atomic number of 6 = 6 neutrons

F) Isotope – Atoms of the same element with different numbers of neutrons. Each Isotope of an element will still have the same numbers of protons

I. Outcome 1 & 2 – Subatomic and the

PTE

A)

SUBATOMIC

– Anything

smaller

than

an atom.

I. Outcome 1 & 2 – Subatomic and the PTE

A) SUBATOMIC – Anything smaller than an atom. The particles that make up an atom.

1) Nucleus –

Dense center of the atom

.

Contains

protons

(+) and

neutrons

(No

charge).

A) SUBATOMIC – Anything smaller than an atom. The particles that make up an atom. 1) Nucleus – Dense center of the atom. Contains protons and neutrons.

--

Nucleon

– particles that make

up the

nucleus

…. Include

1) Nucleus – Dense center of the atom. Contains protons and neutrons.

-- Nucleon – particles that make up the nucleus…. Include protons and neutrons.

2)

Protons

– Nucleon with a

positive

charge. Found in

nucleus

.

atomic mass unit (AMU) of

1

(actual AMU = 1.0073)

1 AMU =

1.66053886 x 10

kg

EQUAL TO

0.00000000000000000000000000166053886 kg

-- Nucleon – particles that make up the nucleus…. Include protons and neutrons.

2) Protons – Nucleon with a positive charge. Found in nucleus.

atomic mass unit (AMU) of 1

3) Neutrons - Nucleon with

no

charge.

Found in

nucleus

.

atomic mass unit (AMU) of

1

but, slightly larger than a

proton

actual Neutron AMU = 1.0087 (Proton’s AMU = 1.0073)

3) Neutrons - Subatomic particle with no charge. Found in nucleus. = 1AMU

but, slightly larger than a proton

actual Neutron AMU = 1.0087 (Proton’s AMU = 1.0073)

-- Responsible for binding

protons

-- Responsible for binding protons together in the nucleus.

4) Electrons - Subatomic particle with

a

negative

charge.

Found

orbiting outside the nucleus

.

AMU of

0.0005

, so small it is

not used to

4) Electrons - Subatomic particle with a negative charge. Found orbiting outside the nucleus. = .0005 AMU

a) Electron Cloud – Area

surrounding

the nucleus

where the

electrons

are

likely to be found.

a) Electron Cloud – Area surrounding the nucleus where the electrons are likely to be found.

+ Includes all energy levels.

b) Energy levels –

Paths

within the

electron cloud

where the electrons

b) Energy levels – Levels within the electron cloud where the electrons orbit the nucleus.

+ Electrons fill energy levels from the

inside-out with this pattern:

Energy level

Maximum electrons it can take

1

_{energy level}

₂

2

_{energy level}

₈

3

_{energy level}

₈

4

_{energy level}

₁₈

5

_{energy level}

₁₈

6

_{& 7}

_levels

_{32 each}

+ Electrons fill energy levels from the inside out with this pattern:

Energy level Maximum electrons it can take 1st _{energy level 2}

2nd _{energy level 8}

3rd _{energy level 8}

4th _{energy level 18}

5th _{energy level 18}

6th _{& 7}th _{levels 32 each}

c)

Valence Electrons

– Electrons in the

last

energy level

.

Electrons that are responsible for most

chemical reactions

.

c) Valence Electrons – Electrons in the last energy level. Electrons that are responsible for most chemical reactions.

5) Quarks – Material that makes up

the

protons and neutrons

.

B) SIMPLE ATOMIC MODEL (not to scale)

++

All

atoms of elements

represented on

the PTE are

electrically neutral

Meaning they have

no electrical

++ All atoms of elements represented on the PTE are electrically neutral Meaning they have no electrical charge (neither + or -).

++

To make the atoms neutral the

protons

(

+

) must equal the

electrons

(

-

).

D) ATOMIC NUMBER & ATOMIC

MASS

1) Atomic Number

– Number of

D) ATOMIC NUMBER & ATOMIC MASS

1) Atomic Number – Number of protons in the nucleus of an atom.

2) Atomic Mass

– Number of

protons

and

neutrons

in the nucleus of an

atom

.

D) ATOMIC NUMBER & ATOMIC MASS

1) Atomic Number – Number of protons in the nucleus of an atom.

2) Atomic Mass – Number of protons and neutrons in the nucleus of an atom.

-- On the periodic table the atomic mass is

given as the

average of the atomic masses

-- On the periodic table the atomic mass is

given as the

average of the atomic masses

of all the

isotopes

of that

element

.

E) COUNTING PROTONS, NEUTRONS

& ELECTRONS.

1) Number of Protons =

Atomic Number

2) Number of Electrons = Number of

protons

(same as the

atomic number

)

3) Number of Neutrons =

Atomic Mass

–

E) COUNTING PROTONS, NEUTRON & ELECTRONS. 1) Number of Protons = Atomic Number

2) Number of Electrons = Number of protons (atomic number) 3) Number of Neutrons = Atomic Mass – Atomic Number

So, the number

Atomic

Mass

(protons and neutrons)

of neutrons =

- Atomic

Number

(protons)

E) COUNTING PROTONS, NEUTRON & ELECTRONS. 1) Number of Protons = Atomic Number

2) Number of Electrons = Number of protons (atomic number) 3) Number of Neutrons = Atomic Mass – Atomic Number

In other words: Atomic Mass (protons and neutrons) - Atomic Number (protons)

Ex: # of neutrons in Carbon?

Atomic mass of

12

– atomic number of

6

=

6

neutrons

Ex Q1: # of neutrons in Mg?

F)

Isotope

– Atoms of the

same element

F) Isotope – Atoms of the same element with different numbers of neutrons.

+ Each Isotope of an element will still have

the

same numbers of protons.

F) Isotope – Atoms of the same element with different numbers of neutrons.

Each Isotope of an element will still have the same numbers of protons.

Ex : Carbon has 16 isotopes….. here are three:

C

12

_{has 6 protons &}

_neutrons

C

14

_{has 6 protons &}

_neutrons,