AP Chemistry 1.1 Laws of Thermodynamics
AP® Chemistry: Laws of Thermodynamics Drill 1, Problem 1. Which equation represents the heat of formation for Calcium Chloride?
| AP Chemistry | Chemical and Physical Properties from Structure and Arrangement Laws of Thermodynamics |
| Language | English Language |
Transcript
We probably want the compound calcium chloride to be on the RIGHT side of the equation...
since that's what's being FORMED. Which means we can immediately eliminate C.
So now to learn what a heat of formation equation...is.
A heat of formation equation shows the elements that make up the compound to be formed, in
their standard state. It's important that they're in their standard
state...which is basically whether they're solid, liquid, or gas at room temperature.
Calcium is a solid at room temperature, and chlorine is a gas at room temperature...
but a diatomic molecule...
Meaning that it looks like Cl 2, not 2 Cl.
These two molecules are in their standard states in option (D).
D's our answer. We haven't had so much fun with formation
since we got that lifetime supply of Play-doh...