Charge questions

1.  What exactly *is* charge?  How do we think of it?  How does this relate to protons and electrons, etc.?

2.  Why is it that electrons are the easiest particles to manipulate?

3.  What does atomic number (Hydrogen = 1, Helium = 2, etc.) mean?

4.  What are quarks?

5.  Coulomb's law is an "inverse square law" - what does this mean exactly?

6.  Why can a charged balloon stick to a wall?

7.  What is "grounding"?

8.  Recall the demonstration where I charged up the small suspended piece - what was I showing?

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