Chem Final
- Instructor enjoyed teaching the class and hopes students appreciate chemistry.
- Open invitation for students to stay in touch.
Final Exam Announcement
- Final exam: Friday, December 5, at 08:30.
- Student feedback for the course is anonymous and appreciated.
Class Structure
- Today's focus: practice problems, with no new content.
- Collaborative problem-solving encouraged.
Practice Problem: Limiting Reactants
- Given: 143.6 g of titanium and 5 moles of diatomic chlorine.
- Task: Calculate moles of titanium tetrachloride produced and identify the limiting reactant.
- Moles of titanium tetrachloride from titanium: 3 moles.
- Moles of titanium tetrachloride from chlorine: 2.5 moles (limiting reactant).
Redox Chemistry Discussion
- Vanadium 2+ acts as reducing agent.
- Zinc 2+ gains one electron, resulting in Zn+.
- Thus, vanadium 2+ is oxidized.
Types of Bonds in Molecules
- O2: only contains covalent bonds; nonpolar covalent due to equal sharing of electrons.
- Rubidium nitrate: contains ionic bond (between rubidium and nitrate) and polar covalent bonds (within nitrate).
Intermolecular Forces
- Types: London dispersion forces, dipole-dipole interactions, hydrogen bonding.
- More intermolecular forces lead to higher boiling points.
Strength of London Dispersion Forces
- All molecules experience London dispersion forces; larger molecules have stronger forces.
- Comparison of diatomic chlorine (Cl2) and carbon tetrachloride (CCl4): CCl4 has a higher boiling point due to larger molecule size.
Bonding and Hybridization
- Increasing bond order leads to decreasing bond length.
- Example: bond lengths compared between single, double, and triple bonds.
- Resonance structures can average out bond orders.