Chapter 7: Radioactivty

Isotope

Element variation

What varies in isotopes?

Neutrons

Unstable nuclei

An atomic nucleus with uneven numbers of protons and neutrons

Decay

The process of stabilizing a nucleus by emitting radiation

What does alpha decay emit?

A helium nucleus

2 protons and 2 Neutrons

What does beta decay emit?

electron

Negative beta decay

Neutron turn proton and emits negative electron

Positive beta decay

Proton turns neutron and emits positive positron

What does gamma decay emit?

pure energy

What is most dangerous internally? Gamma, Alpha, or Beta

Alpha

What is most dangerous externally?

Gamma

Which has longest range?

Gamma

Which has shortest range?

Alpha

What element was Litvinenko poisoned by?

Polonium

How did Poloium kill him?

trough alpha radiation damaging his internal organs

How dangerous is polonium

most dangerous element known

What is half life?

the time it takes for an element to decay to half of its original value

Background radiation

natural ionizing radiation

types of background radiation

cosmic and radon gas

What radiation are Norwegians most exposed to?

Radon

Hormesis

low doses of radiation are beneficial big doses are dangerous

Types of ionizing radiation in medicine

X-ray, PET, MRI, ultrasound

how do x ray work?

outer radiation, x-rays are absorbed by heavy atomic nuclei

Gamma radiation in medicine

source injected into body, gamma cameras outside

What is Bq

Bequerel

What is Gy

Grey

What is Sv

Sievert

What is J

Joule

What does bq meausure

radiation per second/s

What does Sv meausre

health risk from radiation

How much energy is ionizing

more than 10eV