What is the percentage of nitrogen, by mass, in calcium nitrat...

Question

What is the percentage of nitrogen, by mass, in calcium nitrate?

Accepted Answer

Hey there, welcome back. Alright, so here we're going to be calculating the mass percent of oxygen. Okay, Master Sound of oxygen and potassium that hydrogen phosphate have to hydrate. So that's quite a name. Let's go ahead and actually figure out. Break this down, figure out the formula of this compound before we do any calculations. Alright, so potassium potassium is just K. A. Right? I'm sorry, it's just K potassium di hydrogen. So hydrogen, hydrogen and diamonds too. So we're going to have to hydrogen each too. And then we have phosphate, phosphate is a poly atomic iron. It is P 043 minus right? And then help to hydrate. So hydrate, that means we're going to have water molecules around this compound and helped A is a prefix for seven. So we're going to have seven waters in here. So now let's go ahead and put this all together as we can see. Um basically we know exactly what this formula looks like. We know exactly how many of each element. We have. Bills to go ahead and put this all together. So we have a negative three charge here. Whenever phosphate combines with the two waters and the potassium. Remember potassium has a positive one charge two hydrogen, They are also going to have one positive charge each. So that is going to be positive three with a negative three. So that is how we're going to have just all of the charges cancel out. So it's just going to be que each too. P 04. Okay, Q four, that's two and then we have the two waters here, I'm sorry, seven waters. H 20. Alright, so now we're just interested in the mass percent of oxygen. So we have um seven oxygen's here and four oxygen's um there. So in total we have 11 oxygen's. So let's go ahead and actually um calculates the molar mass of this full compound. Okay, so smaller mass Calculation. So we have potassium, we only have one potassium in here. And if you take a look at the product table, it weighs 39.1 g per mole. Then let's do hydrogen is next. So we have two hydrogen right here and then we have seven times to 14. So in total, there are 16 hydrogen in this compound and they weigh one point oh one g each. So this will be 16.16 g for hydrogen. Next we're going to do um phosphorus, there is only one phosphorus And its molar mass is 31 g. Next we have oxygen. And again, oxygen we said we have seven here and then four here. So that's 11 oxygen's in total times a smaller mass, which is 16 g. And that's 1 76. Alright, so we have the molar masses of each of the elements. Let's go ahead and add all of these together. And the molar mass for this whole compound for potassium, the hydrogen phosphate. Help to hydrate is going to be to 62.26 grams per mole. Alright, so we know the total mass of this compound. We also know the mass of oxygen the total mass of oxygen. We can find the mass percent of oxygen. Right? So mass percent Of oxygen is going to equal to the total mass of oxygen. That's going to go on top, which is 1 76 Divided by the total mass of this compound. Where we can find the oxygen, which is this whole compound. And we found a smaller mass. It is to 62 0.26 g. And then everything times 100 to get the percentage. Let's go ahead and divide and multiply. And here our answer will be 67.11%. Right, So that's going to be our final answer for the mass percent of oxygen within this really long compound. Alright folks, I hope you're able to follow along and we'll see you in the next video.

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What is the percentage of nitrogen, by mass, in calcium nitrate?

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