<span>they assign a numerical date to each rock layer studied.</span>
I'm not sure but i would say C.storing the heat energy.
NO₂ is a brown gas while N₂O₄ is colorless. If heating causes a brown color to persist, then this means that heating causes the reaction to shift backwards and produce NO₂. Therefore, the reaction must be exothermic.
Density is not a chemical property. It is a physical property.Electromotive force, Flammability and pH are chemical properties.
