Question 1

Which of the following indicates the existence of strong intermolecular forces of attraction in a liquid?

Accepted Answer

A low vapor pressure indicates that molecules are strongly attracted to each other, meaning that they are less likely to break away from the liquid and move into the gas phase. This is indicative of strong intermolecular forces of attraction. The other options, such as low boiling points, low viscosities, and low enthalpies of vaporization, may indicate weaker intermolecular forces.

Question 2

Which of the following pure substances has the highest normal boiling point?

Accepted Answer

Among the given options, HF has the highest normal boiling point due to the presence of strong hydrogen bonding between the HF molecules. The other options have weaker intermolecular forces, leading to lower boiling points.

Question 3

Which compound has the lowest standard enthalpy of vaporization at 25°C?

Accepted Answer

The enthalpy of vaporization is related to the strength of the intermolecular forces in a substance. A substance with weaker intermolecular forces will have a lower enthalpy of vaporization. Among the choices, compound C (C₅H₁₂), which is pentane, has the lowest boiling point (-129°C) indicating weak intermolecular forces. Therefore, it should have the lowest enthalpy of vaporization.

Question 4

Which of the following pure substances has an unusually high normal boiling point?

Accepted Answer

CH₃NH₂ has an unusually high normal boiling point due to hydrogen bonding between its molecules, which is stronger than the dipole-dipole interactions or London dispersion forces present in the other substances listed.

Question 5

In an experiment,40.0 mmol of helium gas is collected over water.The total volume of gas collected is 0.224 L.Under similar conditions,the gas is collected over two other liquids,A and B.The total volume of gas collected over A and B are 0.222 L and 0.227 L,respectively.Which of the following statements is false?

Accepted Answer

The answer of In an experiment,40.0 mmol of helium gas...

Question 6

Which of the following pure substances has the highest standard enthalpy of vaporization at 25°C?

Accepted Answer

Water (H₂O) has strong hydrogen bonding, which results in a higher enthalpy of vaporization compared to the other substances listed.

Question 7

Which of the following compounds has the highest normal boiling point?

Accepted Answer

The compound with the highest boiling point will have the strongest intermolecular forces. The presence of hydrogen bonding can significantly increase intermolecular forces. Choice C contains an -OH group, which can readily participate in hydrogen bonding, making it the compound with the highest boiling point.

Question 8

Which of the following pure substances has the lowest normal boiling point?

Accepted Answer

The substances listed are H₂S, NH₃, H₂O, H₂Te, and H₂Se, respectively. Among these, H₂S (hydrogen sulfide) has the lowest normal boiling point due to its relatively weak intermolecular forces compared to the others, especially when compared to H₂O, which has strong hydrogen bonding.

Question 9

Rank the following molecules in order of increasing normal boiling point: CH₃CH₂OH,CH₃CH₂CH₂OH,CH₃CH₂OCH₃.

Accepted Answer

The boiling point increases with the strength of intermolecular forces. CH₃CH₂OCH₃ is an ether with weaker dipole-dipole interactions, while CH₃CH₂OH and CH₃CH₂CH₂OH are alcohols with stronger hydrogen bonding. Among the alcohols, CH₃CH₂CH₂OH has a higher boiling point due to its larger size and increased van der Waals forces.

Question 10

Why does hydrogen fluoride have an unusually high normal boiling point compared to the other hydrogen halides?

Accepted Answer

Hydrogen fluoride is capable of forming hydrogen bonds due to the high electronegativity difference between the hydrogen and fluoride atoms. This leads to stronger intermolecular forces and a higher normal boiling point compared to the other hydrogen halides.

Question 11

At 25°C,the vapor pressure of diethyl ether,(CH₃CH₂)₂O,is higher than the vapor pressure of its isomer n-butanol,CH₃CH₂CH₂CH₂OH,because

Accepted Answer

The vapor pressure of a liquid is directly related to the strength of its intermolecular forces. The weaker the intermolecular forces, the higher the vapor pressure. Diethyl ether has weaker intermolecular forces as compared to n-butanol due to the absence of hydrogen bonding in its structure. Hence, diethyl ether has a higher vapor pressure than n-butanol at the same temperature. Therefore, option B is the correct answer. The other options are not directly related to vapor pressure and are not applicable in this case.

Question 12

When two water molecule form a hydrogen bond,which atoms are involved in the interaction?

Accepted Answer

When two water molecules form a hydrogen bond, a partially positive hydrogen atom from one molecule interacts with a partially negative oxygen atom from the other molecule. Therefore, the correct choice is E, a hydrogen from one molecule and an oxygen from the other molecule.

Question 13

Which of the following pure substances has the highest vapor pressure at room temperature?

Accepted Answer

The vapor pressure of a substance is directly proportional to its volatility or tendency to evaporate. Among the given choices, SiH₄ has the highest vapor pressure as it is a small molecule with weaker intermolecular forces compared to the other choices. In contrast, the other choices have larger molecules and/or stronger intermolecular forces, which lower their vapor pressure.

Question 14

Sulfur trioxide (SO₃)is able to be liquefied at low temperatures due to which intermolecular force?

Accepted Answer

London dispersion forces are the weakest intermolecular forces that occur between all molecules, including nonpolar ones like SO3, and are responsible for the ability of SO3 to be liquefied at low temperatures.

Question 15

Which of the following compounds has the highest vapor pressure at 25°C?

Accepted Answer

CH₃CH₂CH₃ (propane) is a non-polar molecule with weak intermolecular forces, leading to a higher vapor pressure compared to the other compounds which have stronger intermolecular forces like hydrogen bonding or dipole-dipole interactions.

Question 16

Which of the following compounds is expected to have the lowest vapor pressure?

Accepted Answer

Compound C (CH3CH2CH2OH) has hydrogen bonding between molecules, which leads to a stronger intermolecular force and a lower vapor pressure. The other compounds do not have hydrogen bonding and will have weaker intermolecular forces and higher vapor pressures.

Question 17

Which of the following compounds has the lowest normal boiling point?

Accepted Answer

The compound with the lowest boiling point will have weak intermolecular forces. Among the given compounds, compound B (which is a fluorocarbon) has the weakest intermolecular forces due to the non-polar nature of the compound and the relatively small size of the fluorine atom. The other compounds have polar covalent bonds or hydrogen bonds, which result in stronger intermolecular forces and higher boiling points.

Question 18

Rank the following in order of increasing normal boiling point: N₂,O₂,Br₂,Xe.

Accepted Answer

The boiling points increase from nitrogen (N2) and oxygen (O2) gases, which are lighter and have weaker intermolecular forces, to xenon (Xe), a noble gas with stronger dispersion forces, and finally to bromine (Br2), a liquid at room temperature with even stronger intermolecular forces.

Question 19

Which one of the following decreases as the strength of the attractive intermolecular forces increases?

Accepted Answer

As the strength of attractive intermolecular forces increases, it becomes more difficult for molecules to break away from each other and escape into the gas phase. As a result, the vapor pressure of the liquid decreases.

Question 20

Which of the following pure substances has the lowest vapor pressure at 25°C?

Accepted Answer

The lower the vapor pressure, the stronger the intermolecular forces of attraction between the molecules. Among the given options, H₂O has the strongest intermolecular forces due to hydrogen bonding between the molecules. Therefore, it has the lowest vapor pressure compared to the other options.

Quiz 11: States of Matter; Liquids and Solids

Which of the following indicates the existence of strong intermolecular forces of attraction in a liquid?

Which of the following pure substances has the highest normal boiling point?

Which compound has the lowest standard enthalpy of vaporization at 25°C?

Which of the following pure substances has an unusually high normal boiling point?

Which of the following pure substances has the highest standard enthalpy of vaporization at 25°C?

Which of the following compounds has the highest normal boiling point?

Which of the following pure substances has the lowest normal boiling point?

Rank the following molecules in order of increasing normal boiling point: CH₃CH₂OH,CH₃CH₂CH₂OH,CH₃CH₂OCH₃.

Why does hydrogen fluoride have an unusually high normal boiling point compared to the other hydrogen halides?

At 25°C,the vapor pressure of diethyl ether,(CH₃CH₂) ₂O,is higher than the vapor pressure of its isomer n-butanol,CH₃CH₂CH₂CH₂OH,because

When two water molecule form a hydrogen bond,which atoms are involved in the interaction?

Which of the following pure substances has the highest vapor pressure at room temperature?

Sulfur trioxide (SO₃) is able to be liquefied at low temperatures due to which intermolecular force?

Which of the following compounds has the highest vapor pressure at 25°C?

Which of the following compounds is expected to have the lowest vapor pressure?

Which of the following compounds has the lowest normal boiling point?

Rank the following in order of increasing normal boiling point: N₂,O₂,Br₂,Xe.

Which one of the following decreases as the strength of the attractive intermolecular forces increases?

Which of the following pure substances has the lowest vapor pressure at 25°C?

Quiz 11: States of Matter; Liquids and Solids

Which of the following indicates the existence of strong intermolecular forces of attraction in a liquid?

Which of the following pure substances has the highest normal boiling point?

Which compound has the lowest standard enthalpy of vaporization at 25°C?

Which of the following pure substances has an unusually high normal boiling point?

Which of the following pure substances has the highest standard enthalpy of vaporization at 25°C?

Which of the following compounds has the highest normal boiling point?

Which of the following pure substances has the lowest normal boiling point?

Rank the following molecules in order of increasing normal boiling point: CH3CH2OH,CH3CH2CH2OH,CH3CH2OCH3.

Why does hydrogen fluoride have an unusually high normal boiling point compared to the other hydrogen halides?

At 25°C,the vapor pressure of diethyl ether,(CH3CH2) 2O,is higher than the vapor pressure of its isomer n-butanol,CH3CH2CH2CH2OH,because

When two water molecule form a hydrogen bond,which atoms are involved in the interaction?

Which of the following pure substances has the highest vapor pressure at room temperature?

Sulfur trioxide (SO3) is able to be liquefied at low temperatures due to which intermolecular force?

Which of the following compounds has the highest vapor pressure at 25°C?

Which of the following compounds is expected to have the lowest vapor pressure?

Which of the following compounds has the lowest normal boiling point?

Rank the following in order of increasing normal boiling point: N2,O2,Br2,Xe.

Which one of the following decreases as the strength of the attractive intermolecular forces increases?

Which of the following pure substances has the lowest vapor pressure at 25°C?

Rank the following molecules in order of increasing normal boiling point: CH₃CH₂OH,CH₃CH₂CH₂OH,CH₃CH₂OCH₃.

At 25°C,the vapor pressure of diethyl ether,(CH₃CH₂) ₂O,is higher than the vapor pressure of its isomer n-butanol,CH₃CH₂CH₂CH₂OH,because

Sulfur trioxide (SO₃) is able to be liquefied at low temperatures due to which intermolecular force?

Rank the following in order of increasing normal boiling point: N₂,O₂,Br₂,Xe.