Radioactivity Flashcards
What are radioisotopes?
Radioactive isotopes of an element. Isotopes keep the same amount of protons and electrons but change in the amount of neutrons.
How are radioisotopes used in cancer treatment?
They use a radioactive drug that seeks out and destroys cancer cells while minimising damage to neighbouring healthy cells.
How are radioisotopes used in food preservation?
By reducing or eliminating microorganisms and insects.
How are radioisotopes used in nuclear reactors?
Radioisotopes can sustain a controlled nuclear chain reaction (when one reaction causes additional reactions).
Why are some isotopes radioactive and others not?
They could have an unbalenced number of neutrons,to many or to little, causing an unstable and therefore radioactive isotope
Describe the characteristics of alpha particles, including penetrating power.
Alpha particles are relatively slow and heavy and can not penetrate skin. Postitivly charged
Describe the characteristics of beta particles, including penetrating power.
Beta particles are small, fast-moving particles with a negative electrical charge, can not penetrate aluminium
Describe the characteristics of gamma rays, including penetrating power.
Gamma rays are the smallest wavelengths and the most energy of any wave. No electrical charge, but is a photon.They can not penetrate masses of lead.
Describe half life.
Half life is used to describe how quickly unstable atoms undergo radioactive decay or how long stable atoms survive (the time required for a quantity to reduce to half of its initial value.)
Define current.
The rate at which electrons flow. Symbol = I
Define voltage.
The pressure from an electrical circuit’s power source that pushes charged electrons (current) through a conducting loop. Symbol = V
Define resistance.
A measure of the opposition to current flow in an electrical circuit. Resistance is measured in ohms Symbol = Ω
What is atomic number?
Number of protons
What is atomic mass?
Number of protons + neutrons
If an atom has 8 protons, how many electrons does it have?
8
How does energy flow through ecosystems?
Primary producers use energy from the sun to produce their own food in the form of glucose, and then primary producers are eaten by primary consumers who are in turn eaten by secondary consumers, and so on
Describe the water cycle.
Liquid water evaporates into water vapor, condenses to form clouds, and precipitates back to earth in the form of rain and snow
What are the basic compomets of the carbon cycle?
Photosynthesis, Decomposition, Respiration and Combustion. Carbon cycles from the atmosphere into plants and living things.
What is the chemical equation for photosynthesis?
6CO2 + 6H2O = C6H12O6 . Water, sunlight and carbon dioxide turns into glucose and oxygen.
Define the role of chlorophyll in photosynthesis.
Chlorophyll’s job in a plant is to absorb light—usually sunlight.
What are the main processes of the carbon cycle?
PHOTOSYNTHESIS (Plants turning CO2 into organic carbon compounds, primarily glucose) AND RESPIRATION (All living organisms, including plants release carbon dioxide into the atmosphere when they respire) AND DECOMPOSITION (During decomposition, organic matter is broken down into simpler compounds, including CO2) AND COMBUSTION (When organic matter, such as fossil fuels (e.g., coal, oil, and natural gas), is burned for energy or during wildfires)
Scientific Method
Change one thing
Measure something
Same, keep everything the same
Independant variable
Dependant Variable
Controls Variables
vir pyramid
V = IxR
I=V÷R
R=V÷I
What did Marrie Currie do?
Discovered radium and polonium. She is remembered her huge contribution to finding treatments for cancer.
