Carbon tetrachloride (ccl4) may be produced when reacting excess chlorine with methane in the presence of light?

CCl4 can be produced by photochemical substitution also called the chlorination of methane 

1. Initiation: chlorine reacts with UV radiation to form a free radical 
Cl2 ===>2Cl·

2. Propagation: the radicals react with the methane with the pattern of...
Radical + Molecule ===> Radical + Molecule 
CH4 + Cl· ===> CH3· + HCl
CH3· + Cl2 ===> CH3Cl + Cl·

3. Termination: this step all the free radicals join to form stable molecules 
2Cl· ===> Cl2
CH3· + Cl· ===> CH3Cl
CH3· + CH3· ===> C2H6

hope that helps 

Both models are effective because they show the valence electrons, and these valence electrons indicate the reactivity of an element.

Answer    "a salt" would be the best answerexplanationsalts can be defined as ionic compounds that are neither acids nor bases. nacl is an example of a salt, and its ionic.an enzyme is an organic compound which is covalently bonded, not ionically bonded.acids are generally held together by covalent bondsan element does not need any bonds to exist