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Learning about Quarks: Go to the website: http://www.quarked.org/ Click on the “SUBATOMIC roadmap” button on the left. Explore the Subatomic Universe Roadmap to answer the following questions. Matter

1.What 3 atoms is a water molecule made of? Two Hydrogen atoms and one oxygen atom

2.How many protons are in each hydrogen atom’s nucleus? One proton in each Hydrogen nucleus. (8 protons in the oxygen nucleus)

3.What type of particle are protons and neutrons? Protons and neutrons are baryons so each has 3 different colour quarks in it.

ANSWER KEY

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The Atom

4.Make a drawing of an atom including: Nucleus, proton, neutron, electron, shell

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Hadrons 5.What are hadrons composed of? Hadrons are particles that are composed of quarks and anti-quarks 6.What are the two kinds of hadrons? The two kinds of hadrons are baryons and mesons.

Baryons are particles that are made of 3 quarks each of a different colour. Example: Protons, Neutrons, Lambdas… (Lambda baryons are hadron particles that contain an up, down and a third quark which can be strange / bottom / charm). The Lambda baryon has also been observed in atomic nuclei called hypernuclei. These nuclei contain the same number of protons and neutrons as a known nucleus. Mesons are particles that are made of a quark (of one colour) and an anti-quark with the anti-colour of the quark). Example: Pions, Kaons

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7. What is special about the three quarks that make up baryons? A baryon is a composite subatomic particle made up of three quarks each of a different colour. In particle physics COLOUR is the name for a property that all quarks have. It refers to the strong force that attracts quarks to each other depending on what color they have (red, blue, or green). This force is transmitted by force particles called gluons. Particles will be stable only when the colors add up to give "white", like the primary colors in art class.

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Quarks are never directly observed or found in isolation; they can be found only within hadrons, such as baryons (of which protons and neutrons are examples) As quark-based particles, baryons participate in the strong interaction, whereas leptons, which are not quark-based, do not. The most familiar baryons are the protons and neutrons that make up most of the mass of the visible matter in the universe.

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A proton is a baryon that has positive electric charge and is found in the nucleus of the atom. It is made of 2 up quarks and a down quark. The number of protons in the nucleus determines what kind of element you have. A neutron is a particle with no electric charge (neutral) made of 2 down quarks and an up quark. It is in the nucleus of most atoms.

Fundamental Particles

8.What are the smallest things that scientists have discovered? The smallest things that scientists have discovered are fundamental particles. So far, no one has been able to split them into smaller pieces. Everything else is made of combinations of these particles.

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9.What are the four types of fermions?

Fermions are particles that cannot exist together if they have identical properties.

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The four types of Fermions are: Quarks (6 of them: Up, down, charm, strange, top, bottom) Leptons (6 of them: Electron, Muon, Tau, electron-neutrino, muon-neutrino, tau-neutrino,) Anti-quarks (6 of them: Anti-Up, Anti-down, Anti-charm, Anti-strange, Anti-top, Anti-bottom) and Anti-leptons (6 of them: Positron, Anti-Muon, Anti-Tau, Anti-electron-neutrino, Anti-muon-neutrino, Anti-tau-neutrino)

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10. What are the force carrier particles? Bosons are particles that can group together even if they have exactly identical properties. Force carrier particles are bosons. Electromagnetic Force: Photons We use the electromagnetic force everyday when we turn on something that uses electricity. We also have compasses that operate using the magnetic force. Electricity and Magnetism at the subatomic scale both are caused by the Electromagnetic force. The carrier of the electromagnetic force is called the photon. We know it in our big world as light. Particles with either positive or negative electric charge are affected by this force. If there is a positively charged particle, it is attracted to the negatively charged one. Two like charged particles repel each other (push each other away). The electrons in the atom are attracted to the protons in the nucleus by this force and that is what holds the atom together. Since neutrons do not have an electric charge, they are not affected by this force (they don't get to shoot photons).

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Weak Force: W Bosons and Z Bosons The Weak force is responsible for what we call radioactive elements. The Weak force also allows the Sun to provide us energy. It allows one element to turn into another one. As its name implies, the weak force is kind of wimpy, but that is because it only happens at short distances. If you are far away from something, the Weak force won't affect you, so we only know about it at the subatomic scale. The Weak force is carried by W and Z bosons. The W bosons each have electric charge, but the Z boson has no electric charge. Neutrinos only interact via this force.

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11. What are the particles that account for the strong force? Strong Force: Gluons

Click on the “Force Carrier Particles” section. It should take you to a screen that talks about forces. Click on the “Strong Force” section Strong Force

12. What part of the atom does the strong force affect? The Strong force holds the nucleus of the atom together. It is hard to break apart a proton to see inside of it because this force is so strong. But the strong force only works with quarks. So electrons don't feel it.

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13. What does a colour charge allow quarks to do? Quarks each have a property called color charge which electrons don't have. So we have 3 different color charges: red, green, and blue that allow quarks to be attracted to other quarks. The carrier of this force is called the gluon.

14. What do gluons do to quarks?

There are actually 8 different kinds of gluons. They can change the color of a quark. These gluons are kind of like rubber bands that hold the quarks together.

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15. What happens to the strong force as quarks

get further apart? What if they get too far apart? As the quarks get farther apart, the strong force actually gets stronger up until a point where things break and new particles are formed.

When you finish all the questions, you may go to the section titled GAME ZONE. Click MORE WEB GAMES AND APPS and try the MATTER MECHANIC game.