Question

The data table below represents the properties determined by the analysis of substances A, B, C, and D.

Substance Melting Point (°C) Boiling Point (°C) Conductivity
A -80 -20 none
B 20 190 none
C 320 770 as solid
D 800 1250 in solution


Which substance is an ionic compound?
a. A
b. B
c. C
d. D

Answer 1

Substance C is likely an ionic compound due to its high melting and boiling points and lack of conductivity as a solid.

Step-by-step explanation:

In order to determine which substance is an ionic compound, we need to analyze the properties of each substance provided in the table. Ionic compounds typically have high melting and boiling points, conduct electricity when dissolved in water, and are often brittle. Based on the provided data, substance C is the most likely to be an ionic compound. It has a high melting point of 320 °C, a high boiling point of 770 °C, and does not conduct electricity as a solid.

Answer 2

Substance D is the ionic compound as it has high melting and boiling points and conducts electricity in solution, matching the typical properties of ionic compounds.

Step-by-step explanation:

To determine which substance is an ionic compound, we must look at the properties provided in the data table concerning melting points, boiling points, and electrical conductivity. Ionic compounds typically have high melting and boiling points, due to the strong ionic bonds between ions, and they conduct electricity when molten or dissolved in solution because their ions are free to move. Comparing the properties of substances A, B, C, and D:

• Substance A does not conduct electricity and has low melting and boiling points, indicating it is not ionic.
• Substance B also does not conduct electricity and has relatively low melting and boiling points, suggesting it is not ionic.
• Substance C has very high melting and boiling points but only conducts electricity as a solid, which is unlikely for ionic compounds.
• Substance D has extremely high melting and boiling points and conducts electricity in solution, matching the characteristics of an ionic compound.

Based on this analysis, substance D is the one that most closely aligns with the properties of an ionic compound. Therefore, the answer to the student's question is (d) Substance D.