The phase diagram for sulfur is shown here. The rhombic and monoclinic states are two solid states with different structures. b. Which of the two solid states of sulfur is more dense?

Video transcript

Hey everyone today, we're being told that a solid can crystallize into two different forms and alpha and a beta form. Using the phase diagram, we're being asked to determine which solid state has is less dense. So let's go ahead and take a look at the Alpha Solid Form 1st. So two things to note is that density, the density rho of a molecule or an element is directly proportional to the pressure exerted upon it. Alright, pressure in red pressure but density is inversely proportional to the temperature, which I read in blue proportional to the inverse of temperature. What this means is that as pressure increases, density of assault will also increase or an object in general and as the temperature increases the density will decrease. So for the sake of this problem, let's assume that we're dealing with a constant pressure. Let's put the pressure right about here, right at the right at the middle ground. It's a very bad line. What do you get what I'm saying? So taking a look at the temperature from T 1 to T two from T 1 to T two. The alpha solid forms at a lower pressure but also at a far lower temperature. However, the bait is solid can only form at higher temperatures than the alpha solid. So since our pressure is constant and debate a solid can only be formed at higher higher temperatures. Then the alpha solid at this pressure. This in turn tells us that the beta solid is less dense, that the beta solid is the less dense equals less dense. I hope this helps. And I look forward to seeing you all in the next one.