Marjorie's unknown substance is sodium chloride NaCl.
The substance is insoluble in CClâ. The density of the substance is 2.2 g/mL.
Solubility:
The fact that the chemical is insoluble in CClâ (tetrachloromethane), as indicated in the statement, indicates that the substance is polar in nature. Only CââHâ of the choices is soluble in CClâ since they are both non-polar by nature and related substances dissolve similarly. CââHâ is therefore disregarded.
Density:
There are now only three possibilities left. SiOâ, FeClâ, and NaCl. The student discovered that the material has a density of 2.20 g/ ml. This is quite similar to sodium chloride's density (i.e., 2.165 g/mL). As a result, sodium chloride is most likely the material the student is working with.
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