How do you convert MOLES to MOLECULES? and MOLES to ATOMS?

How can I convert from moles to molecules,from molecules to atoms and from atoms to grams?

• Okay, in Chemistry I am really getting confused when my teacher goes over converting from moles and stuff. I want to get a good grade on my online homework but it is getting kind f ...show more

• Answer:

  This answer might be a bit tricky to explain with only text, but I'll try my best. Needless to say, stoichiometry is one of the backbones of chemistry, so the best way to learn is to practice as many problems as you can. So.. 1 mole = 6.02 x 10^23 units (units can be molecules or atoms, cars, donuts, anything). This is the Avogadro number. It's sort of like a chemist's dozen. If I have one mole of sodium chloride (NaCl), I have 6.02 x 10^23 molecules of NaCl. If I have 2 moles of NaCl, I have 2 x (6.02 x 10^23) molecules of NaCl. If I only have half a mole of NaCl, I have 0.5 x (6.02 x 10^23) molecules of NaCl. Remember that one molecule has a certain number of atoms that make it up. Water is a simple enough example, so let's look at that. You have to keep the chemical formula in mind when you're converting molecules to atoms, and some questions might ask you only for the amount of hydrogen atoms in say, 3.4 moles of water. Here's how you would solve: 1) Think through the problem, pick out your starting unit and establish your end unit. In this case, we're starting with moles but we want to end up with H atoms. So we're going to have to convert moles --> molecules ---> atoms. 2) Convert moles to molecules. 3.4 mol H2O x (6.02 x 10^23) molecules H2O/mol H2O = 2.0 x 10^24 molecules H2O Notice that the mol H2O units cancelled out; this is because in simple multiplication, if you have identical units in the numerator and denominator, they can just be crossed out. In this case, you're left with molecules H2O in the numerator. Crossing out units correctly is the key to solving stoichiometry problems. 3) Convert molecules to atoms (specifically, hydrogen atoms) 2.0 x 10^24 molecules H2O x 2 H atoms/molecule H2O = 4.1 x 10^24 H atoms (molecules H2O cancelled out) ^^ final answer I'm sorry I can't answer your full question (I've never heard of FU units before, and I've already been through a year of general chemistry in college), but I hope this little bit helped. It's a matter of grasping the concept of conversion factors. Just like you convert SI units (like meters to kilometers and such), you basically do the same thing here. You have to manipulate the units so that when you do the calculations, all of the units except for the end unit cancel out. Good luck!