Marjorie is trying to determine the identity of an unknown substance. after running tests, she determines that the substance is insoluble in ccl4 with a density of about 2.2 g/ml. substance density boiling point solubility (in water) solubility (in ccl4) nacl 2.165 g/ml 1413°c soluble insoluble c10h8 1.14 g/ml 255°c insoluble soluble fecl3 2.898 g/ml 315°c soluble insoluble sio2 2.634 g/ml 2590°c insoluble insoluble using the data above, which of the following substances is most likely marjorie's unknown? a. fecl3 b. nacl c. sio2 d. c10h8

            The substance is most likely NaCl.

Explanation:
                    Solubility:
                                   As stated in statement the substance is insoluble in CCl₄ (Tetrachloromethane), it shows that the substance is polar in nature. In given options only C₁₀H₈ is soluble in CCl₄ because both are non polar in nature and like dissolves like. Hence, C₁₀H₈ is rejected.

                    Density:
                                 Now, we are left with three options. NaCl, FeCl₃ and SiO₂. The student found that the density of substance is 2.20 g.mL⁻¹. Which is very close to the density of NaCl (i.e. 2.165 g.mL⁻¹). Therefore, most probably the substance the student is dealing with is Sodium Chloride.

The mass has escaped into a gas which you can not see so the law stays true.