Question

you are given two unknown solutions, a and b. one of the solutions contains water and table salt, and the other contains water and table sugar. using the data table and your knowledge of chemical bonds, you are able to determine which solution contains sugar and which contains salt. which solution is which?
a. a contains sugar and b contains salt, because salt is ionic and a good conductor of electricity.
b. a contains salt and b contains sugar, because sugar is ionic and is a good conductor of electricity.
c. a contains salt and b contains sugar, because salt is covalent and is a poor conductor of electricity.
d. a contains sugar and b contains salt, because sugar is covalent and is a good conductor of electricity.

	a	b
electrical conductivity in aqueous solution	poor	good
solubility in h₂o (grams of solid in 100 grams h₂o)	3.0	36.0

Explanation:

Step1: Recall properties of salt and sugar

Salt (sodium - chloride) is an ionic compound. Ionic compounds dissociate in water to form ions, which can carry an electric current, so they are good conductors in aqueous solutions. Sugar is a covalent compound and does not dissociate into ions in water, so it is a poor conductor in aqueous solutions.

Step2: Analyze boiling - point and solubility data

The high boiling - point and good electrical conductivity in solution B suggest it contains an ionic compound (salt). The low boiling - point and poor electrical conductivity in solution A suggest it contains a covalent compound (sugar).

Answer:

A. A contains sugar and B contains salt, because salt is ionic and is a good conductor of electricity.