A negatively charged balloon has 3.1 μC of

Question

charge.
How many excess electrons are on this bal-
loon?
Answer in units of electrons.

Answer 1

Divide the balloon charge, -3.1*10^-6 C, by the electron charge, -e = -1.6*10^-19 C

You should get about 1.9*10^13 electrons. That's 19 trillion

Roughly the national debt of the United States!