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Calculate the number of moles represented by each of these: (a) $16.0 \mathrm{~g} \mathrm{Na}$ (b) $0.0034 \mathrm{~g}$ platinum (c) $1.54 \mathrm{~g} \mathrm{P}$ (d) $0.876 \mathrm{~g}$ arsenic (e) $0.983 \mathrm{e} \mathrm{Xe}$

We were trying to figure out how many moles of the compound have We got the first figure out the molar mass of the compound and then convert grams that are no more. So you think periodic table, You just look up the molar mass for each of the I also in the compound and then multiple. I have many, um, as you have and then add it all together. That would be Imola message the compound and then we that convert from very simple. So let me show you what I need. Let's take a water H 20 as an example were first gonna figure out the molar mass of water over his state. See what the molar masses for hydrogen and most like that I choose. Since we have two hydrogen atoms, right, Molar mass for hydrogen is 1.1 grants formal and we have two hydrogen atoms, so that gets more blood. Then you add the mola master oxygen, which is 16. And when you do this way, we get 18.2 grants from old. And since we know that we have four points by rams of where you just, uh, possible slide out with the grants normal, which is the molar Mass. So for one mole of we have 18.2 grand, these grants would just cancel each other out, and he looks those with moles as the unit. So when you basically divide or 0.5 by 18 02 you get 0.25 0.25 more released you up. Let's do a couple more examples. Let's take the example of very and hydroxide remember, savior of the molar mass reach element, and that's going to give us ultimately the molar mass for the entire compound would, you know, by looking at periodic table. So we have one. Very, um, I on And the molar mass from Mariam is 1 37.33 That phrase Add that to the number of oxygen's that we have in the molar mass for oxygen. So we know that we have two oxygen here and the mullahs master, that is 16 grams. We're also going to add that to the hydrogen atomic master molar mass. We have two engines, and the master bed is one point. What? And multiply all this and Advil together we're gonna get 171.35 raised from all of the whole compounds. That's for Berrien outside. Now, Uh, let's see what we know, which is that there's 471.6 grams very hydroxide. We're gonna cross Multiply it by so we know that for every mole for everyone mold, we have 171.35 grams. So now by dividing 471.69 are sorry point. Sit by that by 171 point I can't seem to get those 2.75 Mol bearing hijack side. Let's do 1/3 1 Let's do iron. I think this iron too bossy. Take the molar mass for each element Ridge most like that by how many as we have. So for iron we have three iron mull of as rambles I by the molar mass which is, um, 55.8. And that's great from old then for offi we know that there are two boss eight hours. Sorry. So we're going to multiply two by 30.97 Nothing brings formal. We'll add that to our oxygen's and we see that we have eight Oxygen's here almost five 18 grand. We multiply that all up and added, Together we're going to get 357.49 and that's brands from all of the whole compound. I didn't shoot bossy. Then we will go ahead and cross. Most live that by what we know is the mass in grams, and that's going to give us the mold of this compound. So we know that we have 129.68 grams across most by that bythe mass. So for every one mole of this compound, you have 357 24 9 brands. So when you define 1 29.68 by 3 37.49 you're gonna end up with point every 6 to 8 moles of this iron too bossy

You're determining the number of moles, President, each compound in there, three different compounds You're gonna need the molar mass. And so I have portions of the periodic table over there on the right. You're gonna calculate the molar mass for silver nitrate and you'll get that to be 100 and 69.88 grams per moles. And so 22.6 Divided by that mask is you 0.133 moles of silver nitrate and you do the similar steps for zinc sulfate again. One zinc, one sulfur and four oxygen. That's going to give you a molar mass zinc sulfate of one mole per 601 161.44 grams. And when you calculate that out, you'll get 0.0 403 moles of zinc sulfate identical process here for HCL hydrogen chloride using the molar mass one mole are 1.1 grams of hydrogen plus 35.45 grams of chlorine. That'll give you the molar mass of HCL and you do the math and you get 0.9599 moles. And around that 23 significant figures, you're gonna get 0.960 moles

So for these questions, we'll be using kind of this general formula. It would be the mass without being grams times are moles of whatever our film it is and then the rain. But mm hmm. And I'll get our moles. So this kind of lets us can soffits graham. So start with a We have 16.0 g of sodium. We have our mold on top and we're going to fight By the mass number. So for this first one it's 22 points 99 g. And when we divide that, we get 26 96 moles of sodium. Okay, So that is for our first one now to let her be some were plutonium to Yeah. Yeah. The same one divided by the probably .08 g. And it's a very small number. Okay, There's get for B now we'll move on to see that is 1.5 four g of phosphorus. Uh wait for prosperous is 30.97 g. Okay. Which are males for this week. And fatherless, massive phosphorus down too deep. Yeah, we have 8.76 g. Arsenic. You can't wait Or Arsenic is 74.92 g. Yeah, If I that we get .0117 moles. Yeah. Now we have seen on. And so how he is 3 1.29 Barrios. So that is how many most of grams. You have any malls? You know, that would be for that for those that mass. Yeah

Defend the reaction off a decomposition or spcl five year Spcl three and also CEO too. And also we keep in the, uh, equally in constant and ah liberal mo's off spcl fee and sell to what would be the yearly Be amenable. More off off the porta and reactive. Okay, first of four, we're going to convert Ah lumber most to ah concentration And then we compulsive coagulation. So we just divide the number one most by ah, volume will be ASUs 2.5. So we have so point when one to motor. And also we have ah so ploy. See your 64 motor? Okay, let's step. You're going to establish your eye stable so we have no spc If I just start riff and then we have zero point, we want you and we're still going to see 164 So from here, because we have, we have First of all, you killed IBM. But we don't have any spcl five So you should have You should have spcl free and I'll say it to reality Shoulder that being consumed will get spcl five So we have my sex, my sex and also we have sex. So we have x zero point where and when to Wessex. And then we're still going to see it was 64 my six. Okay, so the Lexx, sadly, we're going to extend British Doug E. Coli berry expression because you see a point when went to you my six times see off 1064 miles, six over X And this expression, you would be close to 2.5 time tendon. That too. We're going, Teoh. Um, way we're going to self the court tactic equation. Okay, so, um okay, so you can sell for that, And then we should be able to find eggs. Ah, you see, cruise to Syria 0.464 more So this will be who Sue aches. So we are going to plugging extruded Westhoff. Our, um I stable. So first of all, for Corinne, it should be equals to see off on a serial 176 moaner. And they were gonna move by that by, um, 2.5 litre to fight the lumber. Mostly correspondents of syrup or 040 Most Okay, so I'm well funds you low sp CEO Phooey! So we have our Siripong went to my soup or so forces for and then we would have 0.656 Motor is Coy's pointing to 0.16 full mole. And that's when all these were half hour Spcl five very close to see upon so 464 motor and you will be chorus pointing to su a porn 116 most and those that they're a month off spcl if I spcl free and also sales here at E. Coli.