 Okay, so, yeah, don't say anything guys, yeah. Just kidding, don't get me wrong. So the number two question on this practice exam is how many hydrogen atoms are present in 0.046 grams of ethanol? Okay, so we know the mass of ethanol. I'll just use that as an abbreviation for ethanol. 0.046 grams. And we know the molecular formula of ethanol, C2H6O. So the first thing we want to do is figure out how many moles of ethanol we have here. So moles of ethanol. So how do we figure that out? Well, we've got to figure out the molecular weight of ethanol. So the molecular weight of ethanol, we just did that problem, remember? So it's going to be 2 times 12.011 AMU, 6 times 1.00794 AMU, 1 times 15.99 AMU. And I'm just using the periodic table that's on the wall, okay? So remember this, of course, is C2H6O. And we add all those up. So how do we figure out the number of moles? Remember the molar mass, we just figured that out. So this is the molecular weight here. The molar mass we can like approximate, right? So the 46.069 grams per mole. So the number of moles of ethanol, we know how many grams of it we've got. 0.046 grams. And you just want to get grams out of there and put moles in. So take that and invert it. 1 mole, 46.069 grams. Grams cancel like that. And I got the number of moles is 9.99, I guess. And we'll do 9.985, right? Times 10 to the negative 4 moles of C2H6O. So that's how many moles of ethanol we have. So now, we want to figure out, well, how many hydrogen atoms do we have per each molecule of ethanol? So we got 6 hydrogen atoms per molecule of ethanol, right? So the number of moles of hydrogen atoms would be 6 times this number here. 9.985 times 10 to the negative 4 moles. So that equals 0.001, whatever, moles of hydrogen atoms. And 1 mole of hydrogen atoms is 6.022 times 10 to the 23rd. So that many moles is that many times 6.022 times 10 to the 23rd. So let's just erase this part here. Can I erase this part, is that cool? So we just take this number, multiply it by 1 mole is 6.022 times 10 to the 23rd. So that equals, so this is atoms. So you get 3.6, well, it's just 2 sick pigs in your initial numbers. So it's going to be 3.6 times 10 to the 21st. We'll say hydrogen atoms and 0.046 grams of ethanol. Okay, does that make sense? Makes sense when you go through it, right?