Exercises: Intermolecular Forces and Properties of Substances
Name the strongest type of intermolecular force present in each substance: (a) $\text{HCl}$, (b) $\text{CH}4$, (c) $\text{H}2\text{O}$.
Name the strongest type of intermolecular force present in each substance: (a) $\text{HCl}$, (b) $\text{CH}_4$, (c) $\text{H}_2\text{O}$.
Classify each substance as ionic, covalent (molecular), or metallic: (a) $\text{NaCl}$, (b) $\text{Cu}$, (c) $\text{CO}2$, (d) $\text{MgO}$.
Classify each substance as ionic, covalent (molecular), or metallic: (a) $\text{NaCl}$, (b) $\text{Cu}$, (c) $\text{CO}_2$, (d) $\text{MgO}$.
Explain the difference between an intramolecular force and an intermolecular force. Give one example of each using water.
Explain the difference between an intramolecular force and an intermolecular force. Give one example of each using water.
The table lists boiling points at 1 atm. | Substance | Boiling point (°C) | |---|---| | $\text{CH}4$ | $-162$ | | $\text{NH}3$ | $-33$ | | $\text{H}2\text{O}$ | $100$ |…
The table lists boiling points at 1 atm.
| Substance | Boiling point (°C) |
|---|---|
| $\text{CH}_4$ | $-162$ |
| $\text{NH}_3$ | $-33$ |
| $\text{H}_2\text{O}$ | $100$ |
Identify the main intermolecular force in each substance and use it to explain the trend in boiling points.
Aaliyah heats two white solids in the lab. Solid A melts at $801\,^\circ\text{C}$ and conducts electricity when molten but not when solid. Solid B melts at…
Aaliyah heats two white solids in the lab. Solid A melts at $801\,^\circ\text{C}$ and conducts electricity when molten but not when solid. Solid B melts at $60\,^\circ\text{C}$ and does not conduct electricity in either state. Classify each solid as ionic or molecular covalent, and explain your reasoning in terms of particles and forces.
Explain why copper can be drawn into wire and conducts electricity, while a crystal of sodium chloride shatters when struck and does not conduct as a solid. Refer to the…
Explain why copper can be drawn into wire and conducts electricity, while a crystal of sodium chloride shatters when struck and does not conduct as a solid. Refer to the type of bonding and the motion of charged particles in each case.
The noble gases and halogens show increasing boiling points down a group. | Substance | Molar mass (g/mol) | Boiling point (K) | |---|---|---| | $\text{F}2$ | 38.0 | 85…
The noble gases and halogens show increasing boiling points down a group.
| Substance | Molar mass (g/mol) | Boiling point (K) |
|---|---|---|
| $\text{F}_2$ | 38.0 | 85 |
| $\text{Cl}_2$ | 70.9 | 239 |
| $\text{Br}_2$ | 159.8 | 332 |
| $\text{I}_2$ | 253.8 | 457 |
(a) Identify the intermolecular force acting in these nonpolar molecules. (b) Explain the trend using electron cloud size and polarizability. (c) Predict whether $\text{HF}$ (molar mass 20.0 g/mol, boiling point 293 K) follows this trend, and explain what additional force accounts for your conclusion.
Marcus must rank four substances by melting point: $\text{MgO}$, $\text{NaCl}$, $\text{CH}3\text{OH}$ (methanol), and $\text{CH}4$. (a) Classify each by bonding type and…
Marcus must rank four substances by melting point: $\text{MgO}$, $\text{NaCl}$, $\text{CH}_3\text{OH}$ (methanol), and $\text{CH}_4$. (a) Classify each by bonding type and name the force that must be overcome to melt it. (b) Rank them from lowest to highest melting point and justify the order. For $\text{MgO}$ versus $\text{NaCl}$, use ion charges (Mg$^{2+}$, O$^{2-}$ versus Na$^+$, Cl$^-$) in your argument. (c) State which of the four you expect to conduct electricity when molten.