Question

On first glance, table salt, $NaCl$, and ordinary table sugar, sucrose, $C_{12}{H}_{22}{O}_{11}$, appear very similar; both are white, crystalline solids.
Of the four possibilities listed below, which one would be a useful test to distinguish between table salt and surcose?
Tasting of chemicals in the laboratory is never an option, so it has not bee included.

• A. Test electrical conductivity in the solid state.
• B. Test to see if the solid is water soluble.
• C. Test electrical conductivity in aqueous solution.
• D. Test the pH of an aqueous solution of the substance.

Answer 1

The correct option is C Test electrical conductivity in aqueous solution.

• The electrical conductivity of solids is due to the motion of electron or positive holes.
• In metals, electrical conductivity is due to the motion of electrons and the electrical conductivity increases with the increase in the electrons available for conduction, the electrical conductivity increases.