Which solid would you expect to have the largest band gap? a. As(s) b. Sb(s) c. Bi(s)

Video transcript

Hey everyone in this example, we need to determine among the given solids below, which would have the widest band gap. So looking at our first option in a we have germanium as a solid. We should recognize that based on its location on the periodic table, germanium is a meta Lloyd. Looking at choice B. We would also recognize that silicon based on its location on the periodic table is also a meta Lloyd. And then looking at option C. We have titanium, which is a metal and we want to recall that medals therefore have small band gaps. And so we would go ahead and rule out choice C since we know that it's a metal with a small band cap. So now we're between germanium and silicon and we want to recall the trend that band gap will decrease as we go down the group number. Or we can say as we go down the column on the periodic table. And so looking at germanium on the periodic table, we see that it lies across period sorry, across period four, whereas silicon lies across Period three on the periodic table. And so because Germanium is lower on the periodic table than silicon, we would say that therefore germanium has a lower or we should say sorry, smaller band gap. And so that would just leave silicon as our only correct choice because we would also rule out choice A where silicon because it is only across period three on the periodic table as a meta Lloyd, it will have the widest band gap. So B is our final answer. To complete this example. If you have any questions, please leave them down below, and I will see everyone in the next practice video.