Lab 3: Boiling Points

Measuring the boiling point of a compound can be used to ________ a. confirm the compound's identity b. determine the compound's structure c. calculate the compound's density d. assess the compound's purity

a. confirm the compound's identity d. assess the compound's purity

What types of intermolecular interactions are present in alkanes? a. van der waals b. ionic c. hydrogen bonding d. dipole-dipole

a. van der waals

What types of intermolecular interactions are present in alcohol? a. van der waals b. ionic c. hydrogen bonding d. dipole-dipole

a. van der waals c. hydrogen bonding d. dipole-dipole

As the temperature you're measuring increases, the difference between the measured temperature and the literature temperature generally decreases. (In other words, these thermometers are generally more accurate at higher temperatures.) a. true b. false

b. false

Non-mercury thermometers are just as accurate as mercury thermometers a. true b. false

b. false

The temperature of a pure boiling liquid is equal to the temperature of the ______ above the liquid a. bubbles b. vapors c. glass d. water

b. vapors

The normal boiling point of a compound is measured at standard pressure, which is equal to ________ or _____

760 mmHg 1 atm

The boiling points in this experiment will be measured using a ______________ setup

Distillation

The boiling point of a liquid is defined as the temperature at which the _____________ of the liquid equals atmospheric pressure

Vapor pressure

Place the following four compounds in order of boiling point from lowest to highest. a. 1-pentanol b. 1-propanol c. 1-hexanol d. 1-butanol

1-propanol > 1-butanol > 1-pentanol > 1-hexanol

Because the boiling point is sensitive to pressure, it is important to record the barometric pressure when determining a boiling point if the determination is being conducted at an elevation significantly above or below sea level. Water boils at ___ °C at sea level, but in Denver (5,000 ft) it boils at __ °C while on Mt. Everest (29,029 ft), boiling water only reaches __ °C.

100 93 72

Place the following four compounds in order of boiling point from lowest to highest. a. 1-pentanol b. 2-butanol c. 3-methyl-1-butanol d. 1-butanol

2-butanol > 1-butanol > 3-methyl-1-butanol > 1-pentanol

Place the following four compounds in order of boiling point from lowest to highest. a. 2-methyl-2-propanol b. 1-propanol c. 1-butanol d. 2-propanol

2-methyl-2-propanol > 2-methyl-2-propanol > 1-propanol > 1-butanol

Place the following four compounds in order of boiling point from lowest to highest. a. Cyclobutanol b. Cycloheptanol c. Cyclohexanol d. Cyclopentanol

Cyclobutanol > Cyclopentanol > Cyclohexanol > Cycloheptanol

Branching in the hydrocarbon chain of an alcohol __________ the boiling point compared to an alcohol with a linear hydrocarbon portion

Decreases

A primary alcohol will have a ________ boiling point than a secondary alcohol with the same number of carbon atoms

Higher