how do you know whether the product is a solid, liquid, or gas at room temperature? What is the balanced chemical equation for the reaction? Regarding when the metallic element sodium combines with...

how do you know whether the product is a solid, liquid, or gas at room temperature? What is the balanced chemical equation for the reaction? Regarding when the metallic element sodium combines with the non metallic element iodine, I2(s).

Expert Answers
ncchemist eNotes educator| Certified Educator

The chemical equation for sodium reacting with iodine is:

2Na + I2 --> 2NaI

Solid metallic sodium combines with solid iodine to produce solid sodium iodide.  Sodium is a group 1 metal and as such it readily loses an electron to become the highly stable sodium cation (Na+).  Iodine is a halogen and as such it readily gains an electron to become the highly stable iodide anion (I-).  The sodium cation and the iodide anion combine to form sodium iodide (NaI).  We know that this is a solid at room temperature since it is an ionic salt and as such has an extremely high melting point.  It is also highly soluble in water.