UNE - Chem 1011 - Midterm Study Guide
Study online at https://quizlet.com/_83tggt
1. A hydrogen bond is characterized by
A. the attraction of temporary dipoles produced by the random asymmetries
in electron motion
B. the electrostatic attraction between the permanent dipoles in any polar
molecule
C. the highly concentrated partial charge between an H atom and F, O, or N
atoms
D. the covalent sharing of electrons between two atoms in a molecule: C. the
highly concentrated partial charge between an H atom and F, O, or N atoms
(Ref: Week 1 Quiz)
A. LDF's
B. Dipole-Dipole
D. Covalent Bond
2. Which of the following will have the strongest dipole-dipole attractions?
A. NCl3
B. CCl4
C. BCl3
D. Cl2: A. NCl3
(Ref: Week 1 Quiz)
Asymmetrical - Usually have a higher dipole moment
Why not BCl3? Because Nitrogen is more electronegative than Boron.
3. A cohesive force
A. is the result of the intermolecular forces that attract identical molecules
, UNE - Chem 1011 - Midterm Study Guide
Study online at https://quizlet.com/_83tggt
B. is the result of the intermolecular forces that attract different molecules
together
C. is the result of covalent interactions between atoms in a molecule
D. is always stronger than an adhesive force: A. is the result of the intermolecular
forces that attract identical molecules
(Ref: Week 1 Quiz)
Easy way to remember. Co = mutual so cohesive is identical molecules.
4. ”Hvap is
A. the energy change when a substance changes from the liquid phase to the
gas phase
B. the energy change when a substance changes from the solid phase to the
liquid phase
C. the energy change when a substance changes from the liquid phase to the
solid phase
D. the energy change when a substance changes from the solid phase directly
to the gas phase: A. the energy change when a substance changes from the liquid
phase to the gas phase
(Ref: Week 1 Quiz)
Liquid ’ Gas (Vaporization)
Ex: Boiling
5. A liquid in a tube will form a convex meniscus when
A. the adhesive forces are stronger than the cohesive forces
B. the cohesive forces are stronger than the adhesive forces
C. the adhesive forces are equal to the cohesive forces
D. it's impossible to predict: B. the cohesive forces are stronger than the adhesive
, UNE - Chem 1011 - Midterm Study Guide
Study online at https://quizlet.com/_83tggt
forces.
(Ref: Week 1 Quiz)
6. In a phase diagram, the critical pressure represents
A. the temperature and pressure when gas, liquid, and solid phases coexist
B. the maximum temperature that a liquid can exist
C. the maximum pressure that a gas can exist
D. the minimum pressure that a solid can exist, regardless of temperature: C.
the maximum pressure that a gas can exist
(Ref: Quiz Week 1)
Key word: pressure, so the answer is either C or D. We know it isn't D because the
critical point of a phase diagram exists near the supercritical fluid area.
7. Molecular solids
A. are composed of positive and negative ions held together by electrostatic
attractions
B. are composed of atoms, with nuclei in a "sea" of delocalized electrons
C. are composed of atoms held together by a repeating network of covalent
bonds
D. are composed of neutral molecules held together by intermolecular forces-
: D. are composed of neutral molecules held together by intermolecular forces
(Ref: Week 1 Quiz)
8. The correct expression to calculate the heat required to convert 100 g of ice
starting at -12 °C to liquid water at a final temperature of 85 °C is:
A. (m x c x ”T)ice + (n x ”Hfus) + (m x c x ”T)water
B. (n x ”Hfus) + (m x c x ”T)water
Study online at https://quizlet.com/_83tggt
1. A hydrogen bond is characterized by
A. the attraction of temporary dipoles produced by the random asymmetries
in electron motion
B. the electrostatic attraction between the permanent dipoles in any polar
molecule
C. the highly concentrated partial charge between an H atom and F, O, or N
atoms
D. the covalent sharing of electrons between two atoms in a molecule: C. the
highly concentrated partial charge between an H atom and F, O, or N atoms
(Ref: Week 1 Quiz)
A. LDF's
B. Dipole-Dipole
D. Covalent Bond
2. Which of the following will have the strongest dipole-dipole attractions?
A. NCl3
B. CCl4
C. BCl3
D. Cl2: A. NCl3
(Ref: Week 1 Quiz)
Asymmetrical - Usually have a higher dipole moment
Why not BCl3? Because Nitrogen is more electronegative than Boron.
3. A cohesive force
A. is the result of the intermolecular forces that attract identical molecules
, UNE - Chem 1011 - Midterm Study Guide
Study online at https://quizlet.com/_83tggt
B. is the result of the intermolecular forces that attract different molecules
together
C. is the result of covalent interactions between atoms in a molecule
D. is always stronger than an adhesive force: A. is the result of the intermolecular
forces that attract identical molecules
(Ref: Week 1 Quiz)
Easy way to remember. Co = mutual so cohesive is identical molecules.
4. ”Hvap is
A. the energy change when a substance changes from the liquid phase to the
gas phase
B. the energy change when a substance changes from the solid phase to the
liquid phase
C. the energy change when a substance changes from the liquid phase to the
solid phase
D. the energy change when a substance changes from the solid phase directly
to the gas phase: A. the energy change when a substance changes from the liquid
phase to the gas phase
(Ref: Week 1 Quiz)
Liquid ’ Gas (Vaporization)
Ex: Boiling
5. A liquid in a tube will form a convex meniscus when
A. the adhesive forces are stronger than the cohesive forces
B. the cohesive forces are stronger than the adhesive forces
C. the adhesive forces are equal to the cohesive forces
D. it's impossible to predict: B. the cohesive forces are stronger than the adhesive
, UNE - Chem 1011 - Midterm Study Guide
Study online at https://quizlet.com/_83tggt
forces.
(Ref: Week 1 Quiz)
6. In a phase diagram, the critical pressure represents
A. the temperature and pressure when gas, liquid, and solid phases coexist
B. the maximum temperature that a liquid can exist
C. the maximum pressure that a gas can exist
D. the minimum pressure that a solid can exist, regardless of temperature: C.
the maximum pressure that a gas can exist
(Ref: Quiz Week 1)
Key word: pressure, so the answer is either C or D. We know it isn't D because the
critical point of a phase diagram exists near the supercritical fluid area.
7. Molecular solids
A. are composed of positive and negative ions held together by electrostatic
attractions
B. are composed of atoms, with nuclei in a "sea" of delocalized electrons
C. are composed of atoms held together by a repeating network of covalent
bonds
D. are composed of neutral molecules held together by intermolecular forces-
: D. are composed of neutral molecules held together by intermolecular forces
(Ref: Week 1 Quiz)
8. The correct expression to calculate the heat required to convert 100 g of ice
starting at -12 °C to liquid water at a final temperature of 85 °C is:
A. (m x c x ”T)ice + (n x ”Hfus) + (m x c x ”T)water
B. (n x ”Hfus) + (m x c x ”T)water
