The EPA defines hazardous materials as having one or more of these characteristics - - Corrosiveness, Radioactivity, Flammability, Poisonous
- Ignitability. Corrosiveness, Reactivity, Toxicity
- Reactivity. Radioactivity, Biohazardous, Ignitability
- Toxicity, Biohazardous, Corrosiveness, Flammability​

Spontaneity tell us the direction of the reaction, but not how fast it goes. gibbs free energy brings together enthalpy, entropy and temperature in one easy formula. g = h - ts. and, finally the sign of delta g is always negative for a spontaneous reaction.

The answer is bhope this

It is a mixture. simply put, a compound must be pure, that is, of only one chemical structure and composition. a mixture is made of different chemical substances (i.e. elements, molecules, compounds) that are not chemically bonded to each other, but instead physically grouped together, as in the case of gasoline (a homogeneous solution).

Ithink carbon dioxide, i am not completely sure.tell me if i am wrong.