CHEM 219 LAB REPORT & NOTES
BUNDLE 2026/2027 | Experiments 1-8
Complete Guide | Portage Learning
Organic Chemistry Lab | Verified
Procedures & Data | Pass Guaranteed -
A+ Graded
EXPERIMENT 1: DISTILLATION (SIMPLE & FRACTIONAL)
Question 1: What is the purpose of adding boiling stones or boiling chips to a
distillation flask?
A) To increase the boiling point of the liquid
B) To provide nucleation sites for smooth boiling and prevent bumping
C) To absorb impurities from the liquid
D) To catalyze the distillation reaction
Correct Answer: B
Rationale: Boiling stones provide nucleation sites for bubble formation, allowing
smooth boiling without sudden violent eruptions of liquid (bumping) that can cause loss
of product or safety hazards .
,Question 2: In fractional distillation, why is a fractionating column packed with
steel wool or glass beads?
A) To increase the volume of the distillate
B) To increase the surface area for repeated vaporization and condensation cycles
C) To absorb water from the vapor
D) To prevent the distillate from overheating
Correct Answer: B
Rationale: More surface area allows more condensation-vaporization cycles (theoretical
plates), improving separation of liquids with closer boiling points. Each cycle increases
the purity of the more volatile component .
Question 3: During a distillation of a methanol-water mixture, which compound
distills first and why?
A) Water distills first because it has a higher density
B) Methanol distills first because it has a lower boiling point (64.7°C) than water (100°C)
C) Both distill simultaneously because they form an azeotrope
D) Neither distills because they are immiscible
Correct Answer: B
Rationale: The lower boiling point component has higher vapor pressure at a given
temperature, so it enriches the vapor phase early in the distillation . Methanol has a
boiling point of 64.7°C, while water boils at 100°C .
,Question 4: Why should you never distill a flask to complete dryness?
A) The flask might crack from the heat
B) Explosive peroxides or other hazardous residues may concentrate and ignite
C) The distillate will become contaminated
D) The thermometer will break
Correct Answer: B
Rationale: Many organic compounds form peroxides upon exposure to air; distilling to
dryness can leave a shock-sensitive residue that may detonate. This is a critical safety
rule in organic chemistry labs .
Question 5: In simple distillation, what is the typical maximum temperature you
would see when distilling pure water?
A) 50°C
B) 75°C
C) 100°C
D) 120°C
Correct Answer: C
Rationale: The boiling point of pure water is 100°C at standard atmospheric pressure.
During distillation, the thermometer at the condenser inlet reads the boiling point of the
distilling vapor .
Question 6: Which type of distillation is best for separating two liquids with
boiling points that differ by less than 40°C?
, A) Simple distillation
B) Fractional distillation
C) Vacuum distillation
D) Steam distillation
Correct Answer: B
Rationale: Fractional distillation uses a fractionating column that provides multiple
theoretical plates, allowing separation of compounds with closer boiling points. Simple
distillation works best for differences greater than 40-50°C .
Question 7: What is the purpose of the "distillation head" or "three-way adapter"?
A) To connect the flask, condenser, and thermometer
B) To heat the flask
C) To collect the distillate
D) To cool the vapor
Correct Answer: A
Rationale: The distillation head (three-way adapter) connects the round-bottom flask to
the condenser and provides a port for the thermometer to measure vapor temperature .
Question 8: Which of the following is a safety hazard specific to distillation?
A) The distillate may be flammable
B) The apparatus may build up pressure if sealed
C) Hot glassware can cause burns
D) All of the above
BUNDLE 2026/2027 | Experiments 1-8
Complete Guide | Portage Learning
Organic Chemistry Lab | Verified
Procedures & Data | Pass Guaranteed -
A+ Graded
EXPERIMENT 1: DISTILLATION (SIMPLE & FRACTIONAL)
Question 1: What is the purpose of adding boiling stones or boiling chips to a
distillation flask?
A) To increase the boiling point of the liquid
B) To provide nucleation sites for smooth boiling and prevent bumping
C) To absorb impurities from the liquid
D) To catalyze the distillation reaction
Correct Answer: B
Rationale: Boiling stones provide nucleation sites for bubble formation, allowing
smooth boiling without sudden violent eruptions of liquid (bumping) that can cause loss
of product or safety hazards .
,Question 2: In fractional distillation, why is a fractionating column packed with
steel wool or glass beads?
A) To increase the volume of the distillate
B) To increase the surface area for repeated vaporization and condensation cycles
C) To absorb water from the vapor
D) To prevent the distillate from overheating
Correct Answer: B
Rationale: More surface area allows more condensation-vaporization cycles (theoretical
plates), improving separation of liquids with closer boiling points. Each cycle increases
the purity of the more volatile component .
Question 3: During a distillation of a methanol-water mixture, which compound
distills first and why?
A) Water distills first because it has a higher density
B) Methanol distills first because it has a lower boiling point (64.7°C) than water (100°C)
C) Both distill simultaneously because they form an azeotrope
D) Neither distills because they are immiscible
Correct Answer: B
Rationale: The lower boiling point component has higher vapor pressure at a given
temperature, so it enriches the vapor phase early in the distillation . Methanol has a
boiling point of 64.7°C, while water boils at 100°C .
,Question 4: Why should you never distill a flask to complete dryness?
A) The flask might crack from the heat
B) Explosive peroxides or other hazardous residues may concentrate and ignite
C) The distillate will become contaminated
D) The thermometer will break
Correct Answer: B
Rationale: Many organic compounds form peroxides upon exposure to air; distilling to
dryness can leave a shock-sensitive residue that may detonate. This is a critical safety
rule in organic chemistry labs .
Question 5: In simple distillation, what is the typical maximum temperature you
would see when distilling pure water?
A) 50°C
B) 75°C
C) 100°C
D) 120°C
Correct Answer: C
Rationale: The boiling point of pure water is 100°C at standard atmospheric pressure.
During distillation, the thermometer at the condenser inlet reads the boiling point of the
distilling vapor .
Question 6: Which type of distillation is best for separating two liquids with
boiling points that differ by less than 40°C?
, A) Simple distillation
B) Fractional distillation
C) Vacuum distillation
D) Steam distillation
Correct Answer: B
Rationale: Fractional distillation uses a fractionating column that provides multiple
theoretical plates, allowing separation of compounds with closer boiling points. Simple
distillation works best for differences greater than 40-50°C .
Question 7: What is the purpose of the "distillation head" or "three-way adapter"?
A) To connect the flask, condenser, and thermometer
B) To heat the flask
C) To collect the distillate
D) To cool the vapor
Correct Answer: A
Rationale: The distillation head (three-way adapter) connects the round-bottom flask to
the condenser and provides a port for the thermometer to measure vapor temperature .
Question 8: Which of the following is a safety hazard specific to distillation?
A) The distillate may be flammable
B) The apparatus may build up pressure if sealed
C) Hot glassware can cause burns
D) All of the above
