There are seven naturally occurring diatomic molecules. What are they?

1 Answer
Apr 10, 2018

Well, five of them are gases, one a liquid, and one a solid at 25^@ "C" and "1 atm". But if you mean which ones actually are found as such,


The five gases are "H"_2, "N"_2, "O"_2, "F"_2, and "Cl"_2, while the liquid is "Br"_2 and the solid is "I"_2. To prove it, here are their respective boiling points at "1 atm":

T_b(H_2) = -252.9^@ "C"
T_b(N_2) = -195.8^@ "C"
T_b(O_2) = -183.0^@ "C"
T_b(F_2) = -188.1^@ "C"
T_b(Cl_2) = -34.04^@ "C"
T_b(Br_2) = 58.00^@ "C"
T_b(I_2) = 184.2^@ "C"

You should be able to say why these show that the molecule is a gas, liquid, or solid at room temperature, i.e. for which of these is T_b > 25^@ "C" (if so, we have a liquid), etc.