7.1 Radioactive decay… and more!

Ft. the Hulk

 What is radioactivity?● The release of high-energy particles and rays of energy from a

substance.○ It gets released in three different ways called radioactive decay…

■ Alpha Decay■ Gamma Decay■ Beta Decay

● Natural Background radiation is the stream of high-energy particles or waves that is found in our environment.○ This radiation can possibly interact with an atom so that it forms

ions.● What is radiation though?

○ Radiation is high energy rays and particles give off by radioactive sources. Some examples are:■ Microwaves■ Radio waves■ Visible light

 RadiationRadiation is a unique thing, it is always there but most is not visible to the human eye… In the picture below the only ones that are visible are “visible light”

●

The Hulk was turned into the Hulk with gamma rays

 Quiz!Which of the following have the highest radiation?● Radiowaves● Microwaves● XRaysNatural Background radiation is where?● In man made objects● In the environment● Doesn’t exist

 The atom...● In an atom as you may know it is composed of 3 different subatomic

particles○ Protons

■ These positively charged particles let you know which element it is.

○ Neutrons■ These have no charge but they help the nucleus stay together.

○ Electrons■ Little negative charged particles that float around the nucleus.

● Now what would happen if we change the amounts of them?

 Let’s change it up!If we add more…● Protons

○ Our element changes to another element.● Electrons

○ The charge of the atom changes● Neutrons

○ You get the Isotope of the element.■ Hold on… what is an isotope….

 Isotopes…● An Isotope happens when an element has different amounts of neutrons.

○ Basically if you take Uranium-235 and you add 3 neutrons you get Uranium-238■ (Hint: the -XXX represents the Mass Number which is the

protons and the neutrons added together.○ Not all Isotopes are stable!!!!!

■ That means that even though neutrons have no charge meaning it does not turn more positive or negative, neutrons have a weight and a roll in the nucleus…

■ Neutrons help hold the nucleus together! Now if you add too much milk to your cereal it will overflow and just fall apart, it is the same with your nucleus.

 Going from unstable...● An isotope that is unstable doesn’t stay unstable, it has something called

a half life, which is the time before the element undergoes some sort of radioactive decay.

● Radioactive decay is the process in which an element goes from unstable to stable. There are three paths that the element can take to decay.○ Alpha decay○ Beta decay○ Gamma decay

 ...To stableSince were dealing with the hulk I will explain Gamma first…● Gamma radiation is made out of high energy rays and short-wavelength

radiation. Now gamma radiation has NO CHARGE and NO MASS this is important to know because when you do an equation with gamma you need to note that there is no change to the element other than the energy (represented by an *)○ eg.

●

https://www.youtube.com/watch?v=X-mq-hFQuQ8

lesson learnt… don’t mess with gamma radiation...

Here’s a little demo

Unless you want to turn out like this guy… green… forever...

● Beta decay is an electron○ But, unlike gamma decay this does give off a particle, this is

because inside the nucleus there is one neutrons that suddenly turns into a proton and an electron.

● Now while the proton stays inside the nucleus the electron shoots out at high speed. ○ This process is easily stopped by a thin sheet of aluminum foil.

● Eg.

Beta Decay

Sadly The Amazing Hulk didn’t partake in beta decay but here just to start off alpha decay here is a quick animation on what it is!

https://www.youtube.com/watch?v=T92V4YtS5x0

No Hulk...

 Alpha decaySadly, The Hulk only underwent gamma decay… now I wonder what would have happened if it would have been alpha decay… hmmm… that makes me wonder what is alpha decay? Well… this guy will explain it very well!

https://www.youtube.com/watch?v=j5TJRtJxVfs

He might have turned out like the red Hulk...

Sadly this is the end… for now...He’ll be back...