Question 1

A molecule of acetylene (C₂H₂) has a ________ geometry and a molecular dipole moment that is ________.

Accepted Answer

Acetylene (C2H2) has a linear geometry due to the sp hybridization of the carbon atoms, and because the molecule is symmetrical, it has a molecular dipole moment of zero.

Question 2

Are the two compounds shown below best described as $\underline{\text{  cis-trans isomers, constitutional isomers,  }}$ or $\underline{\text{ not isomeric?  }}$

Accepted Answer

The answer of Are the two compounds shown below best...

Question 3

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH₃CH₂CH₂CH₂CH₃ or (CH₃)₂CHCH₂CH₃

Accepted Answer

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Question 4

Does 1,1-dichloroethene (Cl₂C → CH₂) have a net molecular dipole moment? If it does, draw the molecule and indicate the direction of this molecular dipole moment.

Accepted Answer

The answer of Does 1,1-dichloroethene (Cl₂C → CH₂) have a...

Question 5

Draw the structure of the isomeric form of 1,2-dichloroethene (CHC–CHCl) which has no net dipole moment.

Accepted Answer

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Question 6

Which of the following has the highest boiling point?

Accepted Answer

The answer of Which of the following has the highest...

Question 7

Which one of the molecules shown below has no net molecular dipole moment?

Accepted Answer

Ethene (H₂C=CH₂) is a symmetrical molecule with a planar structure, and the dipoles cancel out, resulting in no net molecular dipole moment.

Question 8

Which of the molecules below can hydrogen bond to another of the same compound?

Accepted Answer

Hydrogen bonding requires a hydrogen atom that is covalently bonded to a highly electronegative atom (such as nitrogen, oxygen, or fluorine) and another electronegative atom to serve as the hydrogen bond acceptor. Choice C, which represents a molecule with an -OH (hydroxyl) group, can form hydrogen bonds with another molecule of the same kind because the hydrogen in the -OH group can act as a hydrogen bond donor, and the oxygen can act as a hydrogen bond acceptor. Choices A, B, and D do not have this capability as described.

Question 9

Are the two compounds shown below best described as $\underline{\text{ cis-trans isomers, constitutional isomers, }}$   or $\underline{\text{   not isomeric? }}$

Accepted Answer

The answer of Are the two compounds shown below best...

Question 10

Draw the three-dimensional structure of chloroform (CHCl₃) and show the direction of the molecular dipole moment.

Accepted Answer

The answer of Draw the three-dimensional structure of chloroform (CHCl₃)...

Question 11

Which one of the molecules shown below has a net molecular dipole moment?

Accepted Answer

The molecule CHCl has a net dipole moment due to the electronegativity difference between carbon and chlorine resulting in a polar covalent bond. The molecule COS and BeCl2 have polar bonds, but they have a linear molecular geometry resulting in a net dipole moment of zero. The molecule CCl4 has four polar bonds, but they are arranged symmetrically around the carbon atom resulting in a net dipole moment of zero.

Question 12

What intermolecular attractions exist in a pure sample of methylthiol, CH₃SH?

Accepted Answer

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Question 13

Would you expect sodium chloride (NaCl) to be highly soluble in the organic solvent hexane (CH₃CH₂CH₂CH₂CH₂CH₃)? Briefly explain your answer.

Accepted Answer

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Question 14

What intermolecular forces are present among molecules in dimethyl ether, CH₃OCH₃?

Accepted Answer

Dimethyl ether has a bent structure with a polar C-O bond, making it a polar molecule. Hence, it exhibits dipole-dipole attractions. Additionally, it has a non-polar methyl group, which contributes to London dispersion forces. Therefore, both London dispersion forces and dipole-dipole forces are present in dimethyl ether. Hydrogen bonding is not possible as there are no hydrogen atoms bonded to an electronegative atom like nitrogen, oxygen, or fluorine.

Question 15

Does the C – O bond in methanol (CH₃OH) possess an individual bond dipole moment? Briefly explain your answer.

Accepted Answer

The answer of Does the C – O bond in...

Question 16

Are the two compounds shown below best described as $\underline{\text{ cis-trans isomers, constitutional isomers,  }}$ or $\underline{\text{  not isomeric? }}$

Accepted Answer

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Question 17

Provide the condensed formulas of three structural isomers with molecular formula C₅H₁₂ and arrange them in order of increasing boiling point.

Accepted Answer

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Question 18

Which of the following statements is correct?

Accepted Answer

The polarity of a molecule is determined by its molecular geometry and the arrangement of its polar covalent bonds. As such, different arrangements of the same set of atoms can result in variations in polarity. For example, both water (H2O) and hydrogen peroxide (H2O2) have polar covalent bonds, but the bent molecular structure of water results in a permanent dipole moment, while the linear arrangement of H2O2 results in a nonpolar molecule.

Question 19

Which sequence ranks the following isomers in order of increasing boiling points?

Accepted Answer

Isomers 3 and 1 both have hydrogen bonding capabilities, while isomer 2 has only London dispersion forces. Therefore, isomers 3 and 1 will have higher boiling points than isomer 2. Between isomers 3 and 1, isomer 3 has a more linear shape and thus stronger intermolecular forces, leading to a higher boiling point. Therefore, the order of increasing boiling points is 2<1<3, and the best choice is C.

Question 20

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH₃CH₂CH₂OH or CH₃CH₂OCH₃

Accepted Answer

The answer of Which of the molecules below has the...

Quiz 2: Structure and Properties of Organic Molecules

A molecule of acetylene (C₂H₂) has a geometry and a molecular dipole moment that is .

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH₃CH₂CH₂CH₂CH₃ or (CH₃)₂CHCH₂CH₃

Does 1,1-dichloroethene (Cl₂C → CH₂) have a net molecular dipole moment? If it does, draw the molecule and indicate the direction of this molecular dipole moment.

Draw the structure of the isomeric form of 1,2-dichloroethene (CHC–CHCl) which has no net dipole moment.

Which of the following has the highest boiling point?

Which one of the molecules shown below has no net molecular dipole moment?

Which of the molecules below can hydrogen bond to another of the same compound?

Draw the three-dimensional structure of chloroform (CHCl₃) and show the direction of the molecular dipole moment.

Which one of the molecules shown below has a net molecular dipole moment?

What intermolecular attractions exist in a pure sample of methylthiol, CH₃SH?

Would you expect sodium chloride (NaCl) to be highly soluble in the organic solvent hexane (CH₃CH₂CH₂CH₂CH₂CH₃)? Briefly explain your answer.

What intermolecular forces are present among molecules in dimethyl ether, CH₃OCH₃?

Does the C – O bond in methanol (CH₃OH) possess an individual bond dipole moment? Briefly explain your answer.

Provide the condensed formulas of three structural isomers with molecular formula C₅H₁₂ and arrange them in order of increasing boiling point.

Which of the following statements is correct?

Which sequence ranks the following isomers in order of increasing boiling points?

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH₃CH₂CH₂OH or CH₃CH₂OCH₃

Quiz 2: Structure and Properties of Organic Molecules

A molecule of acetylene (C2H2) has a ________ geometry and a molecular dipole moment that is ________.

Are the two compounds shown below best described as cis-trans isomers, constitutional isomers, ‾\underline{\text{ cis-trans isomers, constitutional isomers, }} cis-trans isomers, constitutional isomers, ​ or not isomeric? ‾\underline{\text{ not isomeric? }} not isomeric? ​

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH3CH2CH2CH2CH3 or (CH3)2CHCH2CH3

Does 1,1-dichloroethene (Cl2C → CH2) have a net molecular dipole moment? If it does, draw the molecule and indicate the direction of this molecular dipole moment.

Draw the structure of the isomeric form of 1,2-dichloroethene (CHC–CHCl) which has no net dipole moment.

Which of the following has the highest boiling point?

Which one of the molecules shown below has no net molecular dipole moment?

Which of the molecules below can hydrogen bond to another of the same compound?

Are the two compounds shown below best described as cis-trans isomers, constitutional isomers, ‾\underline{\text{ cis-trans isomers, constitutional isomers, }} cis-trans isomers, constitutional isomers, ​ or not isomeric? ‾\underline{\text{ not isomeric? }} not isomeric? ​

Draw the three-dimensional structure of chloroform (CHCl3) and show the direction of the molecular dipole moment.

Which one of the molecules shown below has a net molecular dipole moment?

What intermolecular attractions exist in a pure sample of methylthiol, CH3SH?

Would you expect sodium chloride (NaCl) to be highly soluble in the organic solvent hexane (CH3CH2CH2CH2CH2CH3)? Briefly explain your answer.

What intermolecular forces are present among molecules in dimethyl ether, CH3OCH3?

Does the C – O bond in methanol (CH3OH) possess an individual bond dipole moment? Briefly explain your answer.

Are the two compounds shown below best described as cis-trans isomers, constitutional isomers, ‾\underline{\text{ cis-trans isomers, constitutional isomers, }} cis-trans isomers, constitutional isomers, ​ or not isomeric? ‾\underline{\text{ not isomeric? }} not isomeric? ​

Provide the condensed formulas of three structural isomers with molecular formula C5H12 and arrange them in order of increasing boiling point.

Which of the following statements is correct?

Which sequence ranks the following isomers in order of increasing boiling points?

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH3CH2CH2OH or CH3CH2OCH3

A molecule of acetylene (C₂H₂) has a geometry and a molecular dipole moment that is .

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH₃CH₂CH₂CH₂CH₃ or (CH₃)₂CHCH₂CH₃

Does 1,1-dichloroethene (Cl₂C → CH₂) have a net molecular dipole moment? If it does, draw the molecule and indicate the direction of this molecular dipole moment.

Draw the three-dimensional structure of chloroform (CHCl₃) and show the direction of the molecular dipole moment.

What intermolecular attractions exist in a pure sample of methylthiol, CH₃SH?

Would you expect sodium chloride (NaCl) to be highly soluble in the organic solvent hexane (CH₃CH₂CH₂CH₂CH₂CH₃)? Briefly explain your answer.

What intermolecular forces are present among molecules in dimethyl ether, CH₃OCH₃?

Does the C – O bond in methanol (CH₃OH) possess an individual bond dipole moment? Briefly explain your answer.

Provide the condensed formulas of three structural isomers with molecular formula C₅H₁₂ and arrange them in order of increasing boiling point.

Which of the molecules below has the higher boiling point? Briefly explain your choice. CH₃CH₂CH₂OH or CH₃CH₂OCH₃