Upload File

nuclear radiation notes. nuclei are unstable when they have low amounts of binding energy. when they...

  • Home
  • Documents
  • Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into
29
Nuclear Radiation Notes

Upload: tyler-hoover

Post on 18-Dec-2015

219 views

Category:

Documents


1 download

Report

Tags:

TRANSCRIPT

Page 1: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

Page 2: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Nuclei are unstable when they have low amounts of binding energy.

• When they are unstable, they are more likely to break into pieces.

Page 3: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Nuclear reactions happen when a change occurs in the nucleus.

• Nuclear Fission is when the nucleus breaks apart in some way

• Nuclear Fusion is when particles combine in some way

Page 4: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• There are many different types of radiation:

• 1. Alpha particle emission--a nucleus could lose an alpha particle, which is essentially the same thing as the nucleus of a helium atom. An alpha particle has two protons and two neutrons, but no electrons (so it has a +2 charge). This is a type of fission.

Page 5: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• A nucleus will tend to undergo alpha particle emission if it is too heavy or it has a low neutron-proton ratio. After alpha particle emission, the resulting nucleus will have a higher N/P ratio, and will be smaller.

Page 6: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes• 2. Beta particle

emission--a beta particle is just like a high speed electron. It has relatively no mass, and has a charge of -1. A nucleus will undergo beta particle emission if it has too high of a N/P ratio, and therefore the resulting nucleus will have a lower ratio. This is also a type of fission.

Page 7: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

• Wait! How can an electron come out of a nucleus, which only contains protons and neutrons?

Page 8: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• This is what you can visualize in your head for how the electron can be emitted from a neutron.

• See what happens to the neutron after the electron (beta-part.) leaves…

http://niels.christoffersen.person.emu.dk/natpr/fysanimat/beta.htm

Page 9: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into
Page 10: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• 3. Gamma ray emission--a gamma ray is a high-energy (high frequency/short wavelength) light wave.

• It has no mass and no charge, and only is emitted at the same time as either alpha or beta particles.

• This is a type of fission

Page 11: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Other less common forms of radiation:

• 4. Positron emission--A positron is essentially the opposite of an electron. It has relatively no mass, but has a charge of +1. Also a type of fission.

Page 12: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• When a positron leaves a nucleus, what is happening is that a proton is losing its charge, and therefore turns into a neutron. Positrons will be released from a nucleus if the N/P ratio is too low.

Page 13: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• 5. Electron Capture--this is a process where an electron loses its energy that keeps it in an energy level, and gets pulled into the nucleus. This is a type of fusion.

Page 14: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• When this happens, the negative charge of the electron cancels out the positive charge of a proton, and the proton is turned into a neutron.

• This has the same effect upon the nucleus as Positron Emission (raises the N/P ratio).

Page 15: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into
http://upload.wikimedia.org/wikipedia/commons/c/c4/Table_isotopes_en.svg
Page 16: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• How do we describe these radioactive occurrences using equations?

• First we need to be able to describe nuclei:

•

• = Uranium with an atomic number of 92 and a atomic weight of 238

Page 17: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Therefore, an alpha particle is:

• or

Page 18: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• A Beta particle can be described as:

• A gamma ray is written simply as:

• A positron is written as:

Page 19: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• A nuclear equation has a direction:

• The arrow signifies which particles existed before the change (reactants) and which ones were present after the change occurred (products)

Page 20: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• In a nuclear reaction, the identity of the elements can change, but the total mass and amount of charge must stay the same. To ensure that our equation shows this, we must balance the equation

• Try example on page 869.

Page 21: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Any single naturally-occurring nuclear reaction will have a specific rate that it happens.

• This rate is measured with a “half-life”, which is the amount of time that it would take for half of a sample of radioactive material to decay naturally.

• The time it would require for a half-life to elapse can be calculated with the following equation: N= No(1/2)n (see pg. 871)

Page 22: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Although radioactive decay (nuclear fission) happens naturally to unstable nuclei, it can also be done artificially (in labs).

Page 23: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• This is called nuclear bombardment, when a particle is put in a collision with another particle, encouraging one or both of them to break apart or stick together.

Page 24: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Oftentimes a nuclear fission reaction will cause a chain reaction with many final products being generated by many separate fission reactions

Page 25: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• This is how most controlled (power plants) fission reactions occur

as well as uncontrolled fission reactions (nuclear explosions)

Page 26: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• The opposite of nuclear fission is nuclear fusion. This is the process where two particles combine to form one nucleus. This will only occur if there is enough energy (heat) and is common on the sun, for instance.

Page 27: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Stability Notes

Page 28: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Most scientists believe that all known elements have arisen from some type of nuclear fusion (mostly in stars).

Page 29: Nuclear Radiation Notes. Nuclei are unstable when they have low amounts of binding energy. When they are unstable, they are more likely to break into

Nuclear Radiation Notes

• Every element above Uranium (#92) has been created by humans using some type of nuclear fusion through bombardment (see pg. 625).


- plusonestudymaterials · 2018-09-11 · Nitrates of both group 1 and group 2 elements are thermally unstable but they decompose differently except LiCO 3 e.g. (b) Carbonates of

Go to Section: Half of a Half of a Half... Some forms of chemical elements are unstable—that is, they break down into other substances. Like the decay

On the convectively unstable nature of optimal streaks in … · 2014-12-22 · On the convectively unstable nature of optimal streaks 223 into turbulent spots. They review the recent

Supernova in a distant galaxy. Many radioactive isotopes are created in the explosion. They are unstable and decay down to stable nuclei. In supernova

Metastable and Unstable Cellular Solidi cation of ...€¦ · Colloidal particles are often seen as big atoms that can be directly observed in real space. They are therefore playing

Microorganisms Are they harmful? Are they beneficial?

They Are Who We Say They Are

Single Player Unstable Unicorns Rules - Unstable Games Wikiunstablegameswiki.com/images/.../Single_Player_Unstable_Unicorns_… · The two core phases are the Action Phase and the

Lunar Grazing Occultations What are they? Why are they Valuable? Are they fun?

Contents innovation and they are living evidence of ... more people are settling in potential danger zones such as on unstable hills ... , are the main reasons why even

The nucleus of the atom is composed of protons and neutrons Some nuclei are stable, some are unstable Larger nucleus = more unstable Smaller nucleus

Type 1 reaction, neuritis and disability in leprosy. What ... · immunological status is unstable.2 They are associated with a delayed type cellular hypersensitivity (DTH) to Mycobacterium

RESEARCH BRIEF | October 2019 It’s About Time...RESEARCH BRIEF | October 2019 Unpredictable and unstable work schedules in re-tail and food service are common, but they are not universal

ORIGIN OF EARTH’S WATER: SOURCES AND CONSTRAINTS · 2019. 12. 11. · of Earth’s water because they are dynamically unstable and can not be traced back to where they formed (Levison

Section 3.1 – Matter, Elements, and Atoms · Radioactive Isotopes • The nuclei of some isotopes are unstable and tend to break down. When they do, the isotope emits energy in

Bonding Atoms are unstable due to their outer e- = valence e-

March 2016 Are markets becoming more unstable? · 2016-04-21 · March 2016 Are markets becoming more unstable? Readers of financial news may believe that ‘market corrections’,

Are resultant methods numerically unstable for Noferini

They are cheerful They are joyful They are happy

WARNING: JOISTS ARE UNSTABLE UNTIL BRACED LATERALLYThis guide is intended for the products shown in dry-use conditions. WARNING: JOISTS ARE UNSTABLE UNTIL BRACED LATERALLY. BRACING

NONVOLATILE PROCESSOR A :EFFICIENT ELIABLE P UNSTABLE … · nonvolatile processor architectures:efficient,reliable progress with unstable power nonvolatile processors (nvps) are

Nuclear Chemistry: The Heart of Matter. 2 Radioisotopes Radioactive decay Radioactive decay – Many isotopes are unstable – Many isotopes are unstable

Mixed Equilibria are Unstable in Games of Strategic ...fede/published/echenique-edlin-JET.pdfMixed Equilibria are Unstable in Games of ... Hofbauer and Hopkins’s papers, the literature

What are they? Where are they? How are they found?

Radioactive Decay Radioactive elements are unstable. They decay, change, into different elements over time. Here are some facts to remember: The half-life

Actin Filaments in Yeast Are Unstable in the Absence of Capping

FEBRUARY 2019 Defiance ETFs · 2019-07-16 · manipulate information in devices called qubits. Qubits are typically unstable and perishable- they maintain their state for around 50

24 TORNADIC EVENTS DURING UNSTABLE: USE OF … · The Alberta foothills are a favorable area to conduct thunderstorm research since they are an area of frequent convective (lightning)

Nuclear Chemistry Chapter 21. Stable vs. Unstable Nuclei 1.Most nuclei are stable – do not change 2.Some nuclei are unstable (radioactive) Change into

Who are they? What are they doing?

Sulfoximines: Structures, Properties and Synthetic ... · thiazyl trifluoride (N ≡SF3).13 They are rather unstable and their exposure to acid, base or heat rapidly rearranges them

What are they? Why are they important? How are they identified?

Software Metrics - Data Collection What is good data? Are they correct? Are they accurate? Are they appropriately precise? Are they consist? Are they associated

Ambisense Sendai Viruses Are Inherently Unstable but Are Useful

Footing and Arena Surface Guide › ... · Round particles create voids and offers cushioning. However, they are typically unstable and can roll like ball bearings, decreasing stability