Which solid would you expect to have little or no band gap? a. Cu(s) b. Si(s) c. As(s)

Video transcript

Hey everyone, we're asked to identify which of the following is expected to have no band gap. Now, as we've learned, metals are expected to have no band gap and therefore these are going to be good conductors. So when we assess our answer choices, we need to find which one is classified as a medal, since semiconductors and insulators both have band gaps. So starting with A we have germanium and we know that germanium is a metal Lloyd. So germanium cannot be our answer since we're looking for a medal and just like pure silicon, pure germanium is a poor conductor of electricity. Looking at B, we have cadmium, cadmium is in fact a medal. So it looks like answer choice B is going to be our answer. But let's go ahead and look at C and D for C. We have selenium and as we know, selenium is a non metal. So C can't be your answer. And lastly looking at phosphorus, we know that phosphorus is a non metal as well. And so this can't be our answer. So our final answer here is going to be be cadmium, which is a metal a good conductor and has no band gap. Now I hope this makes sense. And let us know if you have any questions