Assuming equal concentrations and complete dissociation, arrange ...

Question

Assuming equal concentrations and complete dissociation, arrange these aqueous solutions by their freezing points.

Accepted Answer

Hey there folks. What's up? So here we're going to be arranging the equals solution and increasing freezing point, assuming that they have equal concentrations and completely disassociates. So here all of these ionic compounds and we're going to go ahead and break them up into the ions and figure out how many ions they break up into. And that will be our eye or Van Hoff factor. And here were completely dissociating. So whatever number of ions that associates, that's going to be our I we're assuming that they have the the same concentration. So all we need to look at is their benefactors, their eyes. How many ions they break up into now? What do we know about freezing point? So it's called freezing point depression. That is one of the collective properties. And freezing point is going going to be lowered the more solid concentration we have. Right, So the the higher the solute concentration and a solution, the lower the freezing point becomes right, it's going to get lower and lower and lower more in the negatives, the more solid than we put in. So if we want the these arranged an increasing freezing point, right? Increasing that means we're going to start with the one that has the lowest freezing point, which in turn is going to have the largest solid concentration, which means the largest i in this case. Right, alright, so let's go ahead and take a look. So we have we have sodium and we have sodium nitrate here. So let's go ahead and break up and to their island. So we're going to have sodium plus one and then N. +03 has any give one. So as we can see there's only one sodium and one nitrate. Right? So it's I hear is too next we have aluminum sulfate. Let's go ahead and break them up. So notice that we have two aluminum. So I'm going to write to in front of aluminum and aluminum has a positive three charge because it's in group three and then we have sulfate ion which is so minus. But we have three of them here. Right so there are are ions for aluminum sulfate. So let's go ahead and count two plus three is five. Alright, so so far out of these two this one has the largest i which means going to have the lowest freezing point. Let's go ahead and check the other ones. So we have um potassium pacified. So we have three potassium. I'm going to write three in front of potassium, potassium is positive one And then phosphorus here is in group three a. Um I'm sorry it's it's going to have a negative three. Church. Not in three. Um So that's potassium sulfide and we can see there's only one phosphorus iron. So we have three plus one. And I here is going to equal to four. Okay and then next we have calcium fluoride calcium there's only one calcium ion as we can see it's going to have a positive to charge. And then flooring has a negative one charge rate and there's two of them here so too. Alright so we have one calcium one flooring that means two plus one is going to be three. So let's go ahead and take a look at these numbers. Alright so we said the first one in our arrangement, the one has the lowest freezing point because we're doing it in increasing freezing point. The one has the lowest freezing point will be the one has the highest I which is aluminum sulfide. Right so I'm going to write number one in front of this one. So that would be the first one and then we're going to be an increasing so it's going to be like this right, increasing increasing increasing order. Then the next one would be obviously the one that has lower I. Which will be this one. So this will be number two in our arrangement. Right, yep. And then we have three. So that would be number three and then finally the one that has the lowest I is going to have the lowest solute concentration and the highest freezing point compared to these four. Okay, so this one will be number four. Alright, so that would be our arrangements right there I'm gonna go ahead and highlight them so you can see it. There we go. Alright if you have any questions about this please let us know and we'll see you in the next video

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Assuming equal concentrations and complete dissociation, arrange these aqueous solutions by their freezing points.

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