FTCE Chemistry SAEPreparation Course

Session 2

Lisa BaigInstructor

Course OutlineSession 1

Review Pre TestCompetencies 1 & 2

Session 2Competency 5

Session 3Competency 3

Session 4Competency 4

Session 5Competencies 6, 7 and 8

Post Test

Session Norms

• Respect– No side bars– Work on assigned materials only– Keep phones on vibrate– If a call must be taken, please leave the

room to do so

Homework Review

Any questions from last night?

Chemistry Competencies1. Knowledge of the nature of matter (11%)2. Knowledge of energy and its interaction with matter

(14%)3. Knowledge of bonding and molecular structure (20%)4. Knowledge of chemical reactions and stoichiometry

(24%)

5. Knowledge of atomic theory and structure (9%)

6. Knowledge of the nature of science (13%)7. Knowledge of measurement (5%)8. Knowledge of appropriate laboratory use and

procedure (4%)

73Li

42He 1

1HAtomic Number Mass Number

Element Symbol

Two Key Numbers• Atomic Number

– # of Protons in an atom– This determines the type of

element you have!– If atom is electrically neutral,

then the number of electrons is also equal to this number

• Mass Number– # of protons + neutrons in an

atom’s nucleus– Mass # - atomic # = # of

neutrons

How many protons, neutrons and electrons?

• Iodine-128• 41

20Ca

• 20882Pb4+

• 8135Br1-

• Cobalt-60

S Orbital

• Orbital that can contain 2 electrons

• Spherical in Shape

P Orbitals• Orbital that can contain

up to 6 electrons• Contains 3 sub-orbitals,

each holding 2 electrons

• “Peanut” or “Dumbbell” shaped

D Orbital• Orbital that can contain

up to 10 electrons• Contains 5 sub-orbitals

that can each hold 2 electrons

F Orbital• Orbital that can contain up to

14 electrons• Contains 7 sublevels each

holding 2 electrons

SD-1

P

F-2

1s2s 2p3s 3p 3d4s 4p 4d 4f5s 5p 5d 5f6s 6p 6d7s 7p8s

This is the order used to

place electrons- follow the arrows to

their “end”, then move to

the next arrow

Find the Arrangements for:

• Sulfur• Strontium• Copper• Lead• Radon

Alkali Metals• HIGHLY Reactive Metals• 1 valence electron

– Filling their “S” orbital• Do not occur naturally in nature as

elements– ALWAYS found in compounds

• React with water with increasing violence as atomic number increases

Alkaline Earth Metals• 2 valence electrons• Fill their “S” orbitals• Do not occur in nature as elements

– ALWAYS in compounds• Less reactive than the Alkali Metals

Al

Ga

In

Tl

Sn

Pb Bi

Transitional Metals• Most have 2 valence electrons

– These fill their “D” sublevels• Harder and more brittle than the other

metals• High melting and boiling points• Good heat and electrical conductors• Hg- the ONLY metal to be in the liquid

state at room temperature• Often have colored compounds

Lanthanide Series• Elements Ce thru Lu• Once called the “Rare Earth Metals”• Fill their 4f orbitals• All elements within this section have

amazingly similar chemical and physical properties– This lead to the difficulty in identification of

the elements in this section

Actinide Series• Elements Th thru Lr• Fill their 5f orbital• All elements are radioactive• Beyond Uranium, these elements

have been artificially created

B

Si

Ge As

Sb Te

Po At

Metalloids/Semi-Metals

• All are solids at room temperature• Semi-conductors of heat and

electricity• Some metal properties and non-

metal properties• Fill their “P” level electrons

Non-Metals

• Poor (Non) Conductors of heat and electricity

• Reactive• Diatomic Elements• Gas

– Nitrogen, Oxygen, Hydrogen• Solid

– Carbon, Phosphorus, Sulfur, Selenium

Halogens

• Diatomic Elements or found in compounds

• HIGHLY Reactive• Gases= Fluorine, Chlorine• Liquid = Bromine• Solid = Astatine, Iodine

Noble Gases

• Non-Reactive• We have FORCED it to react and form

compounds with Fluorine• Uses:

– Neon, Argon, Krypton and Xenon are used for lighting

– Helium is used in balloons

Break Time

Take a 10 minute

break!

Calculating

C = l x v

C = Speed of Light3 x 108 m/s

l = wavelengthv= frequency

Practice

What is the frequency of a wave whose wavelength is 4.5x10-5m?

• C = l x v• 3x108m/s= 4.5x10-5m •v• 3x108m/s = 4.5x10-5m= 6.7 x 1012 Hz

What’s a Quantum??

The amount of energy that can be gained or lost by an atom

E = h x vE = Energy of Quantum

h = 6.626 x 10-34 J•s (Planck’s Constant)v = frequency of the wave

Practice

• What is the energy of a wave whose frequency is 2.5x10-4Hz?

• E = h x v• E= (6.626 x 10-34 J•s)(2.5x10-4Hz)• E=1.65x10-37J

Conversions of Mass and Energy

E = mC2

E = Energy m = massC = Speed of Light (3 x 108 m/s)

Practice

• What is the mass of a particle whose energy is 2.41x10-27J?

• E = mC2

2.41x10-27J = m(3 x 108 m/s)2

2.68x10-44kg

Break Time

Take a 10 minute

break!

Unstable Nuclei

Radioactive DecaySpontaneous disintegration of a nucleus into a

smaller sized nucleusNuclear RadiationParticles emitted by a decaying nucleus

All elements above #83 on the Periodic Table

Two Categories

FissionWhen a heavy nuclei splits into

more stable nuclei of intermediate mass

FusionWhen low mass nuclei combine to

form a heavier more stable nucleus

Types of Particle DecayParticle Symbol What stops this particleProton 1

1p A few sheets of paperNeutron 1

0n A few centimeters of leadBeta

Particle(electron)

b-, 0-1b, 0

-1eA few sheets of aluminum foil

Positron b+, 0+1e

A few sheets of Aluminum Foil

Alpha Particle

42He, a, a2+ Skin or one sheet of paper

Gamma Ray

00g, g Several centimeters of lead

Nuclear Reactions42

19K 0

-1e + ?

4240

Ca239

94Pu ? + 235

92U

42He

2713

Al + 42He 30

15P + ?

10n

? + 10n 142

56Ba + 91

36Kr + 31

0n

23592

U

Half-LivesRemaining Mass = half-life fraction

Total Mass1 = ½ 2 = ¼ 3 = 1/8 4 = 1/16

5 = 1/32 6 = 1/64 7 = 1/128 8 = 1/256

# h.l = time elapsed time of 1 h.l

Amount remaining = (original)(1/2)#h.l

Practice

How much of a 100.0g sample of Gold-198 remains after 8.10 days if its half life is 2.70 days?

12.5gA 50.0g sample of 14N decays to 12.5g in

14.4 seconds. What is its half-life?7.2 seconds

Homework

• Diagnostic Exam in your AP chem Prep book- Page 17-26

• Only answer the questions for these Chapters & Questions– Chapter 5 #1, 3, 5– Chapter 10 #32-35– Chapter 17 #81-84