Table salt can be separated into sodium and chlorine. Sodium is explosive. Chlorine is a gas that can kill people. What can be concluded from the statements above? A. A harmful compound can become harmless when its elements are separated. B. A harmless compound can become harmful when its elements are separated. C. Breaking a compound into its separate elements has no noticeable effects. D. Breaking a compound into its separate elements can create carbon dioxide.

The answer is B because sodium chloride is table salt which we commonly consume everyday therefore it is harmless (unless you consume a very high amount) but once you separate them, they become deadly.

B. A harmful compound can become harmful when its elements are seperated.

Explanation:

In the question, common table salt, NaCl was the illustration.

NaCl is a crystalline solid whjch has different benefits like for preservation, add taste to foods etc. NaCl is generally consumed by humans daily and is found readily. This goes to show that NaCl is a harmless compound but the individual elements that is, Soduim and Chlorine gas,

2Na + Cl2 - -> NaCl

Soduim metal is a reactive and unstable element with 1 (valence) electron in its outer shell. Hence why the reaction of sodium strips with water is explosive.

Chlorine gas is very poisonous, unstable as well as reactive because of the 7 (valence) electrons in its outermost shell.