Nuclear Transformations, Radioactivity and Radiation Flashcards
What is the nucleus of an atom made up of?
Protons and neutrons
What does the atomic number represent?
The number of protons in an atom
What is the number of protons equal to?
The number of electrons
What does the atomic mass number represent?
The number of neutrons and protons in an atom
Why are the nuclei able to stay stable?
The force of attraction between particles is stronger than the force of repulsion between protons
The larger a nucleus, the greater the force of __________, so the _____ stable the nucleus
Repulsion, less
Elements with atomic numbers greater than 83 are unstable, what tends to happen to them? What does this cause?
They tend to become atoms of smaller elements and this causes the release of radiation from certain atoms
What are isotopes?
Variations of elements that have the same number of protons but different number of neutrons (atomic mass changes)
What is the half-life of an isotope?
The time it takes for half the amount of a given element to decay into another element
What is radiation?
Energy traveling in the form of particles or waves in bundles called photons
What is radioactivity?
Unstable atoms of an element emit excess energy in the form of waves or particles called ionizing radiation
When does ionization occur?
When high-energy radiation interacts with and removes electrons of an atom of some materials
When isotopes decay they emit _______, in the form of ________ ________.
Energy, ionizing radiation
What are the three types of ionizing radiation?
Alpha decay, beta decay, gamma rays
What can ionizing radiation do to your body?
Tear away electrons from atoms, damaging cells and DNA material
What are alpha particles?
2 protons and 2 neutrons bound together and are identical to a helium nucleus
When are alpha particles emitted?
During the radioactive decay of large atoms
Alpha particles are the most _______ and the least ________
Ionizing, penetrating
What are beta particles?
Excess neutron in the nucleus is converted into a proton and an electron. The proton stays in the nucleus while the electron gets ejected
What are gamma rays produced by?
The radioactive decay of nuclei as they go from a high-energy state to a low-energy state
Are gamma rays particles?
No, they are bursts of energy
Gamma rays are the least _______ and the most ________
Ionizing, penetrating
Which type of radiation is most dangerous inside the body?
Alpha radiation is the most dangerous because it can likely be absorbed by the cells while beta and gamma radiation will pass right through the body
Which type of radiation is most dangerous outside the body?
Alpha radiation are the least dangerous because they can be easily blocked, while beta and gamma radiation can penetrate the skin
When does radiation poisoning occur?
When people are exposed to high amounts of ionizing radiation
What damage does radiation poisoning cause?
Causes the cells to be damaged or to degrade
What does acute and chronic mean, in context with radiation poisoning?
Acute-very soon after high levels of exposure
Chronic-months-years after low levels of exposure
What are some examples of radiation poisoning?
Nuclear bombs, nuclear disasters, intentional administration, accidental exposure
What happens during nuclear fission? What does this cause?
The nucleus of an atom splits into smaller nuclei and releases neutrons and a large amount of energy. The neutrons smash into other atoms and creates more fission, possibly causing a chain-reaction
Why do nuclear power plants use radiation?
To generate steam, to create heat, to generate electricity
The heat used in the nuclear power process is generated by _________ ________.
Controlled fission
Nuclear power plants are ________ and ________ as long as there aren’t any accidents or nuclear meltdowns.
Efficient, non-polluting
How do accidents at power plants usually occur?
By a series of accidental events which allows contaminated material to escape
When and where does nuclear fusion occur?
In stars when two nuclei collide to form one heavier nuclei
Why is nuclear fusion very hard to recreate?
Since it requires very high temperatures
In stars, what 2 isotopes of hydrogen fuse together to form helium? What does this process release?
- Deuterium and tritium
- Neutrons and energy in the form of heat and light
What happens after all the hydrogen in stars gets used up?
The next elements fuse together until only iron is left
What does the star become when all the nuclear fuel is used up? What happens next?
- White Dwarf
- When it is too big, it explodes, this is called a supernova
The bigger the star, the shorter the life span. Why?
It uses up energy quicker
What are some medical/scientific applications?
X-ray crystallography, therapy, diagnostic, and radioisotopes
What are some naturally-occurring isotopes that we are exposed to every day?
Carbon-14, radon-222
Cosmic rays are mostly blocked by the ____ _______. Higher you are in _______, the more you are exposed to cosmic radiation.
- Earth’s atmosphere
- Altitude
What does a geiger counter do?
Used to detect radioactivity
