Chem 130 Exam 2: Key Topics, Organic Nomenclature, and Acid-Base Chemistry

What is the exam date for Chem 130 Exam 2?

November 4th

What materials should you bring to the Chem 130 Exam?

Calculator, physical ID, writing utensils, erasers, and a handwritten cheat sheet.

What type of exam format will be used for Chem 130 Exam 2?

Paper exam with multiple choice questions.

What are the topics covered in the Chem 130 Exam 2?

Lewis Structures, Formal Charge, VSEPR & Polarity, Molecular Solubility, Organic basics & Functional Groups, Energy (Exothermic & Endothermic), IUPAC naming, Alkanes, Alkenes, Alkynes, Alcohols, Carboxylic Acids, Equilibrium, Acid-Base/Conjugates, Ka, pH, Neutralizations, Carboxylic Acids & Amine Properties.

What is the molecular geometry of CH4O around the C atom?

Tetrahedral

How many polar bonds are present in CH4O?

Two polar bonds (C to O and O to C).

Is CH4O a polar or nonpolar molecule?

Polar, because the oxygen atom is more electronegative than carbon.

What types of intermolecular forces (IMFs) are present in polar molecules?

Dispersion, dipole-dipole, and hydrogen bonding.

What is the strongest type of IMF present in water?

Hydrogen bonding.

What is the general formula for naming organic compounds?

Identify the longest parent chain, branches/substituents, high priority groups, assign lowest numbers, and arrange substituents alphabetically.

What is the difference between exothermic and endothermic reactions?

Exothermic reactions release energy, while endothermic reactions absorb energy.

What is the combustion reaction for methane?

CH4 + 2O2 → CO2 + 2H2O + energy.

What is the formula for photosynthesis?

6CO2 + 6H2O + energy (sunlight) → C6H12O6 + 6O2.

What are the functional groups that should be recognized for IUPAC naming?

Aldehyde, Ester, Ether, Amine, Carboxylic acid, Ketone, Alcohol, Aromatic, Amide.

What is the importance of drawing Lewis structures?

They help visualize the bonding and formal charges in molecules.

What is the electron geometry around the O atom in CH4O?

Tetrahedral.

What is the significance of formal charge in Lewis structures?

It helps determine the most stable structure by minimizing formal charges.

Which molecule is most likely to dissolve in water: CH4, CH3OH, or CO2?

CH3OH, because it is polar and can form hydrogen bonds with water.

What is the role of lone pairs in determining molecular geometry?

Lone pairs affect the shape and angles of the molecular geometry.

What is the boiling point trend for polar molecules compared to nonpolar molecules?

Polar molecules generally have higher boiling points due to stronger IMFs.

What are the three types of IMFs present in NH3?

Dispersion, dipole-dipole, and hydrogen bonding.

What is the significance of the root word in IUPAC naming?

It indicates the longest carbon chain in the compound.

What is the definition of a high priority functional group in organic chemistry?

A functional group that takes precedence in numbering the carbon chain.

What is the IUPAC name for the compound with the structure of 2-methylpent-1-ene?

2-methylpent-1-ene

How do you name a carboxylic acid using the IUPAC system?

Find the longest chain containing the COOH group, change the '-e' ending of the parent alkane to '-oic acid', number the chain to put the COOH group at C1, and apply all other nomenclature rules.

What is the IUPAC name for the compound 4-bromo-3-methylhexanoic acid?

4-bromo-3-methylhexanoic acid

What is the general formula for naming alcohols?

Count the carbon chain, start from the side closest to the alcohol, name substituents, add the number where the alcohol is located, and replace the 'e' with 'ol'.

What is the IUPAC name for 4-bromopentan-2-ol?

4-bromopentan-2-ol

What is the structure of cyclohexanol?

Cyclohexanol is a six-membered carbon ring with an -OH (hydroxyl) group attached.

What is the IUPAC name for 3-methylpent-2-ene?

3-methylpent-2-ene

What is the IUPAC name for 2,5-dimethylhex-3-ene?

2,5-dimethylhex-3-ene

What is the IUPAC name for 5-ethyl-3-heptyne?

5-ethyl-3-heptyne

What is the IUPAC name for 4-methyl-octa-1,5-diyne?

4-methyl-octa-1,5-diyne

What is the IUPAC name for 4,4-dimethyl-2-pentyne?

4,4-dimethyl-2-pentyne

What is the total ionic equation for the reaction of HBr and LiOH?

H+ (aq) + Br- (aq) + Li+ (aq) + OH- (aq) → H2O (l) + Li+ (aq) + Br- (aq)

What is the net ionic equation for the neutralization of HBr and LiOH?

H+ (aq) + OH- (aq) → H2O (l)

What happens to the reaction if K = 0.82 and Q = 1.34?

The reaction is not at equilibrium; it must shift left to make more reactants.

What are conjugate acid-base pairs in the reaction of HBr with water?

HBr (acid) and Br- (conjugate base); H2O (base) and H3O+ (conjugate acid)

What is the boiling point trend for primary, secondary, and tertiary amines?

Primary and secondary amines have higher boiling points due to hydrogen bonding; tertiary amines have lower boiling points because they lack N—H bonds.

How does the boiling point of carboxylic acids compare to alcohols?

Carboxylic acids have higher boiling points than alcohols of similar mass due to stronger intermolecular hydrogen bonds.

What is the pH of a 0.045M solution of HCl?

pH = 1.35

What is the pOH if pH = 3.10?

pOH = 14 - 3.10 = 10.90

What is the pKa if pH = 1.35?

pKa = 2.21, indicating it is acidic.