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.

Which of the following statements is true about energy quantization at the atomic level? electrons in the outermost orbits are the most stable. electrons in all the orbits around the nucleus have the same amount of energy. electrons in the orbit closest to the nucleus have the least amount of energy. electrons absorb or release the same amount of energy independent of the energy levels.