How many molecules are there in 0.029 moles of carbon dioxide gas, CO2?

Answer 1

ah, I guess this is sort of a trick question.
Saying you have a mole of something is like saying you have a dozen of them.
Except a mole means about 6*10^23 of them, not twelve of them.
So
you have .029 * 6 * 10^23 molecules

That 6*10^23 (closer to 6.022*10^23) is called Avogadro's number.