Unit 5 HW #3: Bonding Review

Which test will help distinguish between an ionic crystal and molecular crystal?

• Does the substance conduct as a solid?

• Does the substance dissolve in water?

• Does the substance dissolve in water and conduct?

• Is the substance a solid at room temperature?

Which test will help identify a metallic substance from a network substance.

• Is the substance a solid at room temperature?

• Does the solid dissolve in water?

• Does the solid have a metallic luster?

• Does the solid conduct electricity?

Which test will help identify if a substance is a molecule or an ionic crystal?

• Is the substance a white crystal?

• Does the solid conduct electricity?

• Does the solid have a low melting point?

• Does the solid dissolve in water?

Classify the unknown substance using information from the table:

What is Substance A?

• Substance A is a metal because it conducted as a solid.

• Substance A is ionic because it dissolved in water and the solution was conductive.

• Substance A is a metal because it dissolved in solution.

• Substance A is a molecule because it dissolved in water.

Classify the unknown substance using information from the table:

What is Substance B?

• Substance B is a metal because it conducted as a solid.

• Substance B is ionic because it did not dissolve in solution.

• Substance B is a molecule because it had a low melting point and did not dissolve in water.

• Substance B is a network substance because it did not conduct as a solid or molten.

Classify the unknown substance using information from the table:

What is Substance C?

• Substance C is a metal because it did not dissolve in water.

• Substance C is a metal because it has a high melting point.

• Substance C is a network substance because it does not melt, dissolve, or conduct.

• Substance C is ionic because it does not conduct as a solid.

Classify the unknown substance using information from the table:

What is Substance D?

• Substance D is a molecule because it does not dissolve in water.

• Substance D is a metal because it conducts as a solid.

• Substance D is a network substance because it has a high melting point.

• Substance D is ionic because it has a high melting point.

Classify the unknown substance using information from the table:

What is Substance E?

• Substance E is a molecule because it does not dissolve well in water.

• Substance E is a metal because it has a high melting point

• Substance E is network because it conducts.

• Substance E is ionic because it dissolved in water and conducted.

Which has the higher melting point?

In the following pair of substances, based on bond type, which will have the higher melting point?

• N-O

• Cs-Cs

In order to predict properties, like melting point, we need to first identify the bond type present.

Classify the bonds present in the following substances:

Groups:

(a) Metallic

,

(b) Molecular

,

(c) Ionic

,

(d) Network

• Na-Na

• Be-Br

• Cs-Cl

• Cs-Cs

• Si-Si

• H-O

• Fe-Ni

• N-O

• H-H

• P-Cl