Little is known about the chemistry of astatine (At) from direct observation, but reasonable predictions can be made.

(a) Is astatine likely to be a gas, a liquid, or a solid?

Video transcript

All right. Hi, everyone. So this question says that Tennessine is a synthetic element. Therefore, very little empirical data on its properties is available is Tennessine more likely to be a gas, a liquid or a solid option A says solid. Option B says liquid and option C says gas. Now recall that Tennessine resides in group seven A of the periodic table and group seven A is composed of floury chlorine, bromine, iodine as the team and lastly, Tennessine on the bottom of the group itself. Now, in order to answer this question, we can observe the trend or the other elements in group seven A to make a reasonable assumption. And what we'll notice is that the trend as we go down group seven A is that the first few elements are gasses followed by liquids, followed by solids. Because if we take into consideration, fluorine and chlorine, both fluorine and chlorine exist as gas whereas bromine exists as a liquid. Now recall that iodine and acetin are believed to exist as a solid, right, iodine does exist as a solid, whereas acetate is predicted to exist as a solid due to this trend. Now, if we consider Tennessine at the very bottom of the group, the two elements before Tennessine were solids as well, which means that it's reasonable to predict that Tennessine would exist as a solid as well. Meaning that our answer is going to be option A in the multiple choice. Tennessine is more likely to be a solid because of the trend observed going down group 78. So with that being said, thank you so very much for watching. And I hope you found this helpful.