True, if you have rough surface the more friction you have. The More slipery, less friction.
The teacher would use a dozen eggs and a dozen jellybeans to describe a mole.
A mole is simply a <em>number</em> of things.
Just as a dozen eggs is the <em>same number</em> as a dozen jellybeans, a mole of eggs is the <em>same number</em> as a mole of jellybeans.