Molecules And Matter and Radiation Flashcards
What happens to pressure when temperature increases?
The pressure increases because the particles collide more.
When volume of a gas is decreased, what happens to pressure?
Less space, meaning higher pressure.
Who devised an alpha particle scattering experiment?
Rutherford, Geiger and Marsden.
What did the alpha experiment show?
Most passed straight through - empty space.
Some were deflected - charge
Some were deflected at large angles - large mass in nucleus.
What happens to potential energy when a substance changes state?
It increases.
Irradiation
Something exposed to ionising radiation. It can be used to clean materials and tools. This is often a wanted process.
Contamination
The unwanted presence of materials containing radioactive atoms.
How does a radioactive tracer work?
A radioactive isotope emits radiation, which is absorbed by the organ. A gamma camera detects the radiation which bounces back.
How is gamma used to treat cancer?
A narrow beam of radiation penetrates deep into the body and targets a small area.
What is a major source of background radiation?
Radon gas in the ground, as well as food, drink, nuclear weapons testing and medical applications like x-rays.
What do fuel rods contain?
A radioactive substance like uranium.
What does the effect of radiation depend on?
- The dose
- Exposure time
- Whether the source is inside or outside the body.
How can we protect from radiation?
- Keeping as far away as possible.
- Minimise exposure time.
- Use shielding such as a thick concrete wall or thick lead plates.
