Which of the following statements incorrectly uses Avogadro's number? 1. There are 6.022 X1023 carbon atoms in a mole of carbon.
2. There are 6.022 X1023 sodium atoms in a mole of sodium carbonate, Na2CO3.
3. There are 6.022 X1023 formula units in a mole of sodium carbonate, Na2CO3.
4. There are 6.022 X1023 molecules in a mole of carbon dioxide, CO2.