 So, when you are asked to name covalent or molecular compounds, it's a little different than naming ionic compounds like we just talked about. Remember with ionic compounds, you just say the names of the two ions, and then drop the ending of the anion and put ID. But with covalent compounds, you've got to tell the number of the actual atoms in there. So let's try some of these covalent compounds or molecular compounds. So this first one, silicon and oxygen, right, but there's two oxygens for every silicon. So you don't, so you say silicon, if there's only one of the first element that's listed, you just write the element itself. So silicon, but there's two oxygens, so you say di-oxide, okay, so let's try this one. So this one has two nitrogens, so we don't just put nitrogen in it, we put di-nitrogen. What's the prefix for five, pent, drop the A. More than one, that's just carbon.