unit 1: nuclear chemistry review by mrs. billings

Unit 1: Nuclear Unit 1: Nuclear Chemistry ReviewChemistry Review

By Mrs. BillingsBy Mrs. Billings

Brief Overview:Brief Overview:

• Structure of the atomStructure of the atom• Identifying types of decay (alpha, Identifying types of decay (alpha,

beta, gamma) & how nucleus beta, gamma) & how nucleus changes with eachchanges with each

• Nuclear reaction equationsNuclear reaction equations• Nuclear fission vs. nuclear fusionNuclear fission vs. nuclear fusion

Structure of the Atom Structure of the Atom

How would you describe the How would you describe the nucleus? nucleus?

Nucleus is small but dense!! Atom mostly empty space.

IsotopesIsotopes

• Isotopes are atoms with the Isotopes are atoms with the same number of protons but same number of protons but different number of neutronsdifferent number of neutrons

Practice: Practice: – Determine the number of protons and Determine the number of protons and

neutrons in Krypton-86 neutrons in Krypton-86

Answer:Answer:

• Mass number is 86, atomic number is Mass number is 86, atomic number is 36.36.

• Protons = 36Protons = 36• Neutrons = 86 - 36 = 50Neutrons = 86 - 36 = 50

• What is this called when it has a What is this called when it has a different mass from the one of the different mass from the one of the periodic table?periodic table?

What keeps nucleus What keeps nucleus together?together?

+ and + Repel + and + Repel

• Why doesn’t the nucleus’ protons Why doesn’t the nucleus’ protons repel each other and leave? repel each other and leave?

• - Strong Nuclear Force keeps it - Strong Nuclear Force keeps it together. together.

Why do things radiate? Why do things radiate?

Rutherford’s ExperimentRutherford’s Experiment

Types of DecayTypes of Decay• Alpha RadiationAlpha Radiation

– Nucleus loses 2 protons and 2 neutrons Nucleus loses 2 protons and 2 neutrons (alpha particle)(alpha particle)

– Has a +2 chargeHas a +2 charge– Can be blocked by paper or clothingCan be blocked by paper or clothing

Example:Example:226226

8888Ra → Ra → 2222228686Rn + Rn + 44

22HeHe

Types of Decay Types of Decay continued…continued…• Beta RadiationBeta Radiation

– A neutron turns into a proton and A neutron turns into a proton and gives off an electron (beta particle)gives off an electron (beta particle)

– Has a –1 chargeHas a –1 charge– Can be blocked by metal foilCan be blocked by metal foil

Example:Example:1414

66C → C → 141477N + N + 00

-1-1ββ

Types of Decay Types of Decay continued…continued…

• Gamma RadiationGamma Radiation– Each gamma ray has no mass and no Each gamma ray has no mass and no

charge and no particles; it’s just pure charge and no particles; it’s just pure energy!energy!

– Account for almost all the mass lost in Account for almost all the mass lost in radiationradiation

– Not completely blocked by lead or Not completely blocked by lead or concreteconcrete (BUT GAMMA, IT’LL KILL YOU!!!)(BUT GAMMA, IT’LL KILL YOU!!!)

Example:Example:238238

9292U → U → 2342349090Th + Th + 44

22He + He + 2 2 0000γγ

Radiation ChartRadiation Chart

TypeType SymbolSymbol

Alpha decayAlpha decay 4422 He He

Beta decayBeta decay 00-1-1 β β

Gamma decayGamma decay 0000 γ γ

Positron emissionPositron emission 0011 β β

Electron captureElectron capture 00-1-1 e e

Proton Proton 1111 p p

Neutron Neutron BombardmentBombardment

1100 n n

Types of DecayTypes of Decay

• Identify type of decay:Identify type of decay:– A. alpha, B. beta, C. gamma, D. positron, E. A. alpha, B. beta, C. gamma, D. positron, E.

electron captureelectron capture

141466C C 1414

77N  +  N  +  00-1-1ββ  

111166C C 1111

55B  +  B  +  0011ββ  

228228 8686 Rn   Rn       4422He + He + 224224

8484PoPo1414

66C + C + 00-1-1 e → e → 1414

55NN

Nuclear Reaction Nuclear Reaction EquationsEquations

• Nuclear Reaction Equations:Nuclear Reaction Equations:– Calculating the new compound or types Calculating the new compound or types

of decay involved.of decay involved.Practice Problems:Practice Problems:

121277N N ?  +  ?  +  00

11ββ   1414

77N → ? + N → ? + 00-1-1ββ

2262268888Ra → ? + Ra → ? + 44

22HeHe

Decay SeriesDecay Series

Practice Predicting Practice Predicting Radiation Radiation

TypeType SymbSymbolol

When it occursWhen it occurs

Alpha decayAlpha decay 4422 He He When atoms too heavy (>83)When atoms too heavy (>83)

Beta Beta decaydecay

00-1-1 β β Too many Neutrons

Gamma Gamma decaydecay

0000 γ γ

Positron Positron emissionemission

0011 β β Too many protons

Electron Electron capturecapture

00-1-1 e e

ProtonProton 1111 p p BombardmentBombardment

NeutronNeutron 1100 n n Bombardment (like in Bombardment (like in

nuclear fission) nuclear fission)

Fusion vs FissionFusion vs Fission

• Nuclear Fusion:Nuclear Fusion:– Two smaller nuclei are coming together Two smaller nuclei are coming together

to form one larger, more stable nucleus.to form one larger, more stable nucleus.– Examples of Sun and Hydrogen bomb.Examples of Sun and Hydrogen bomb.

• Nuclear Fission:Nuclear Fission:– One large nuclei splits into two smaller One large nuclei splits into two smaller

and more stable nuclei.and more stable nuclei.– Examples of nuclear power plant and Examples of nuclear power plant and

atomic bomb.atomic bomb.

Binding Energy Binding Energy

NUCLEAR JEOPARDYNUCLEAR JEOPARDY

DirectionsDirections• Circle desks into teams of 4Circle desks into teams of 4• Get a whiteboard & sock/marker to shareGet a whiteboard & sock/marker to share• Come up with the answer in your group, Come up with the answer in your group,

making sure other groups don’t hear you.making sure other groups don’t hear you.• Write the answer on your whiteboard and Write the answer on your whiteboard and

hold up toward teacher when done. hold up toward teacher when done. • First group done with correct answer gets First group done with correct answer gets

points.points.• Rotate the whiteboard to the next person in Rotate the whiteboard to the next person in

the group.the group.

Question 1Question 1

• What are the 3 main types of nuclear What are the 3 main types of nuclear radiation?radiation?

Question 1: AnswerQuestion 1: Answer

• AlphaAlpha• BetaBeta• GammaGamma• (positron)(positron)• (electron capture)(electron capture)

Question 2Question 2

How would you stop Beta How would you stop Beta radiation?radiation?

Question 2: AnswerQuestion 2: Answer

Metal foilMetal foil

Question 3Question 3

What type of decay is the What type of decay is the following equation?following equation?

1311315353I I 131131

5454Xe + Xe + 00-1-1ββ

Question 3: AnswerQuestion 3: Answer

1311315353I I 131131

5454Xe + Xe + 00-1-1ββ

Beta DecayBeta Decay

Question 4Question 4

What is missing in the What is missing in the equation?equation?

1313 77N --->  N --->  4422He   + _____He   + _____

Question 4: AnswerQuestion 4: Answer

1313 77N --->  N --->  4422He   + He   + __ 9 9

55B B __

Question 5Question 5

What is missing?What is missing?

3311H   H       33

22He  + ______He  + ______

What type of decay is it?What type of decay is it?

Question 5: AnswerQuestion 5: Answer

3311H   H       33

22He  + He  + __ 0 0-1-1β β __

Beta decayBeta decay

Question 6Question 6

• What is it called when a nucleus What is it called when a nucleus splits apart and releases massive splits apart and releases massive amounts of energy?amounts of energy?

Question 6: Answer Question 6: Answer

• Nuclear fissionNuclear fission

Question 7Question 7

• Which releases more energy fission Which releases more energy fission or fusion?or fusion?

• Give a real-life example of it to prove Give a real-life example of it to prove why.why.

Question 7: AnswerQuestion 7: Answer

• FusionFusion

• The sun or hydrogen bombThe sun or hydrogen bomb

Question 8Question 8

• When will atoms become When will atoms become radioactive?radioactive?

Question 8: AnswerQuestion 8: Answer

• When there are too many protons When there are too many protons and neutronsand neutrons

• When there is an uneven amount of When there is an uneven amount of protons and neutrons.protons and neutrons.

Question 9Question 9

• What keeps the nucleus from falling What keeps the nucleus from falling apart?apart?

Question 9: AnswerQuestion 9: Answer

• Strong Nuclear ForceStrong Nuclear Force

Question 10Question 10

• What makes up the majority of the What makes up the majority of the atom’s mass?atom’s mass?

• What makes up the majority of the What makes up the majority of the atom’s volume?atom’s volume?

Question 10: AnswerQuestion 10: Answer

• Mass= nucleus (protons & neutrons)Mass= nucleus (protons & neutrons)

• Volume= empty space (nothing)Volume= empty space (nothing)