1. All the… small things
Atoms and such

2. Brainstorm
With your group:
What do you know about atoms?

3. What is a quark?
Quarks are particles that make up parts of an atom (protons, neutrons, etc.)
Up Quarks have a charge of + 2/3
Down Quarks have a charge of -1/3
proton
neutron

4. How big is a quark?
A quark has a diameter of about meters (one femtometer)
This means to get the size of a quark, you need take 1/10 of a meter stick repeating 15 times!

5. What about an electron? An electron is made of leptons.
A lepton is a particle that does not experience the strong interaction (that is, the strong nuclear force).
This is why electrons “orbit” the nucleus.
A lepton is about 1/2000 the size of a proton.
What is a real life representation of that relative size?

6. So how big is a hydrogen atom?
Hydrogen- diameter of 50×10−12 m (50 picometers)
What is a physical representation that compares 50 picometers with a hydrogen nucleus that has the diameter of three quarks (3 x m)?
All of that extra “stuff” in an atom is empty space!!!

7. How big is the biggest atom?
Cesium is the largest atom with a known size
260 picometers (260×10−12 m )
Compare that with the size of a hydrogen atom
How does this ratio compare with hydrogen atom to quark ratio?

8. Your assignment Develop visual model that:
Compares a hydrogen nucleus to a hydrogen atom
Compares that hydrogen atom with a grain of sand (one mm diameter).
Compares that grain of sand with a baseball (2.9 inch diameter).
(the hydrogen nucleus should be represented with a visible object)