Title: Chapter 7: Chemical Bonding and Molecular Geometry
Course: Test

Q: According to the octet rule, a magnesium atom has a tendency to _____.
- lose one electron.
- lose two electrons.
- gain one electron.
A: lose two electrons.

Q: A molecule that has a single covalent bond is _____.
- CO_2
- CO
- Cl_2
A: Cl_2

Q: A diatomic molecule with a triple covalent bond is _____.
- O_2
- F_2
- N_2
A: N_2

Q: Which of the following diatomic molecules is joined by a double covalent bond?
- Cl_2
- O_2
- N_2
A: O_2

Q: Which of the following pairs of elements can be joined by a covalent bond?
- N and C
- Na and C
- Mg and C
A: N and C

Q: Which one of the following elements does not exist as a diatomic molecule in nature?
- hydrogen
- nitrogen
- neon
A: neon

Q: Which of the following is an ionic compound?
- CO
- HCl
- Na_2O
A: Na_2O

Q: Which one of these compounds is an ionic compound?
- Na_2O
- CO_2
- N_2
A: Na_2O

Q: According to VSEPR theory, the shape of an ammonium ion, NH_4^+, is most similar to __________.
- CH_4
- BH_3
- N_2
A: CH_4

Q: According to periodic trends, which element is the most electronegative?
- Ne
- O
- F
A: F

Q: What is the electron group (EG) and molecular geometry (MG) of an ammonium ion?
- (EG) tetrahedral and (MG) tetrahedral
- (EG) tetrahedral and (MG) trigonal pyramidal
- (EG) tetrahedral and (MG) bent
A: (EG) tetrahedral and (MG) tetrahedral

Q: What is the electron group (EG) and molecular geometry (MG) of an ammonia molecule?
- (EG) tetrahedral and (MG) tetrahedral
- (EG) tetrahedral and (MG) trigonal pyramidal
- (EG) tetrahedral and (MG) bent
A: (EG) tetrahedral and (MG) trigonal pyramidal

Q: According to the octet rule, which of elements will have a tendency to loss 2 electrons?
- strontium
- oxygen
- cesium
A: strontium

Q: Which of the following molecules has the greatest bond energy?
- H_2
- N_2
- O_2
A: N_2

Q: What type of bond will typically form between boron and hydrogen based on their electronegativity?
- metallic
- ionic
- covalent
A: covalent

Q: Based off periodic trends, which of the following has the strongest lattice energy?
- aluminum chloride
- calcium chloride
- sodium chloride
A: aluminum chloride

Q: Construct the molecule IF_5 using a molecular modeling software such as Spartan or 3D-ChemDraw. What are the bond angles of the equatorial fluorine’s in the structure?
- 90°
- 120°
- 109.5°
A: 90°

Q: Construct the molecule IF_5 and PF_5 using a molecular modeling software such as Spartan or 3D-ChemDraw. How do the molecular shapes differ?
- In IF_5 there is a lone pair of electrons on iodine where as in PF_5 there are no lone pairs on phosphorus. As a result, the molecular shape of IF_5 is square pyramidal and PF_5 is trigonal bipyramidal.
- In PF_5 there is a lone pair of electrons on phosphorus where as in IF_5 there are no lone pairs on iodine. As a result, the molecular shape of PF_5 is square pyramidal and IF_5 is trigonal bipyramidal.
- In IF_5 there is a lone pair of electrons on iodine where as in PF_5 there are no lone pairs on phosphorus. As a result, the molecular shape of IF_5 is octahedral and PF_5 is trigonal bipyramidal.
A: In IF_5 there is a lone pair of electrons on iodine where as in PF_5 there are no lone pairs on phosphorus. As a result, the molecular shape of IF_5 is square pyramidal and PF_5 is trigonal bipyramidal.

Q: Construct the molecule PF_5 using a molecular modeling software such as Spartan or 3D-ChemDraw. What are the bond angles of the equatorial fluorine’s in the structure?
- 90°
- 120°
- 109.5°
A: 120°

Q: Construct the molecule PF_5 using a molecular modeling software such as Spartan or 3D-ChemDraw. What are the bond angles of the axial fluorine’s in the structure?
- 90°
- 120°
- 109.5°
A: 90°

Q: Using VSEPR theory, predict the molecule shape of a molecule that contains 2 electron groups.
- trigonal planar
- linear
- bent
A: linear

Q: Using VSEPR theory, predict the electron group geometry, molecular shape, and the bond angles in a molecule that contains 4 electron groups (3 bonds and 1 lone pair electrons).
- tetrahedral, trigonal pyramidal, > 109.5°
- tetrahedral, trigonal pyramidal, < 109.5°
- tetrahedral, trigonal pyramidal, 109.5°
A: tetrahedral, trigonal pyramidal, < 109.5°

Q: Using VSEPR theory, predict the electron group geometry, molecular shape, and the bond angles in a molecule that contains 5 electron groups (2 bonds and 3 lone pair electrons).
- trigonal bipyramidal, linear, 180°
- trigonal bipyramidal, trigonal bipyramidal, 90° and 120°
- trigonal bipyramidal, trigonal bipyramidal, 180°
A: trigonal bipyramidal, linear, 180°

Q: Using VSEPR theory, predict the electron group geometry, molecular shape, and the bond angles in a molecule that contains 6 electron groups (5 bonds and 1 lone pair electrons).
- octahedral, octahedral, 90°
- octahedral, square planar, 90°
- octahedral, square pyramidal, 90°
A: octahedral, square pyramidal, 90°

Q: Using VSEPR theory, predict the molecular shape and bond angles in BCl_3.
- trigonal planer, 120°
- trigonal pyramidal, 120°
- trigonal bent, 120°
A: trigonal planer, 120°

Q: Construct the molecule H_2O using a molecular modeling software such as Spartan or 3D-ChemDraw. What are the bond angles in the structure?
- 104.5°
- 107°
- 109.5°
A: 104.5°

Q: Construct the molecule NH_3 using a molecular modeling software such as Spartan or 3D-ChemDraw. What are the bond angles in the structure?
- 104.5°
- 107°
- 109.5°
A: 107°

Q: Construct the molecule CH_4 using a molecular modeling software such as Spartan or 3D-ChemDraw. What are the bond angles in the structure?
- 104.5°
- 107°
- 109.5°
A: 109.5°

Q: The bond angles in CH_4, NH_3, and H_2O are 109.5°, 107°, and 104.5°, respectfully. Which of the statements best describes the variance in bond angles?
- CH_4 has no lone pairs of electrons on the central atom so the optimal molecular shape would be tetrahedral with bond angles of 109.5°. In NH_3 and H_2O there are 1 and 2 lone pairs, respectfully, so more repulsion exists between the bonds and lone pairs, as a result, the bond angles are less than 109.5°.
- NH_3 and H_2O have a trigonal pyramidal and bent molecular shape, respectfully, which is the reason why the bond angles are less than 109.5°.
- CH_4 only has nonpolar bonds while NH_3 and H_2O have polar bonds which results in the difference in bond angels.
A: CH_4 has no lone pairs of electrons on the central atom so the optimal molecular shape would be tetrahedral with bond angles of 109.5°. In NH_3 and H_2O there are 1 and 2 lone pairs, respectfully, so more repulsion exists between the bonds and lone pairs, as a result, the bond angles are less than 109.5°.

Q: Based off the following data, what is the lattice energy of sodium chloride?

ΔH_sub of Na = 108 kJ/mol

D_o of Cl_2 = 243 kJ/mol

IE of Na(g) = 496 kJ/mol

EA of Cl(g) = -349 kJ/mol

ΔH_f of NaCl = -411 kJ/mol
- -1490 kJ/mol
- -909 kJ/mol
- -788 kJ/mol
A: -788 kJ/mol

Q: In an ionic bond, the charge on the cation (i.e. the metal) is
- always positive.
- always negative.
- either positive or negative.
A: always positive.

Q: According to the octet rule, a magnesium atom has a tendency to
- lose one electron.
- lose two electrons.
- gain one electron.
A: lose two electrons.

Q: A covalent bond is formed when two atoms
- share an electron with each other.
- share one or more pairs of electrons with each other.
- gain electrons.
A: share one or more pairs of electrons with each other.

Q: According to the octet rule, a bromine atom has a tendency to
- lose one electron.
- lose two electrons.
- gain one electron.
A: gain one electron.

Q: The halogens have how many valence electrons?
- 4
- 6
- 7
A: 7

Q: How many electrons are shared in a single covalent bond?
- 2
- 3
- 1
A: 2

Q: How many electrons are shared in a double covalent bond?
- 3
- 4
- 2
A: 4

Q: A molecule that has a single covalent bond is _____.
- CO_2
- CO
- Cl_2
A: Cl_2

Q: A diatomic molecule with a triple covalent bond is _____.
- O_2
- F_2
- N_2
A: N_2

Q: Which of the following diatomic molecules is joined by a double covalent bond?
- Cl_2
- O_2
- N_2
A: O_2

Q: Which of the following pairs of elements can be joined by a covalent bond?
- N and C
- Na and C
- Mg and C
A: N and C

Q: _____ is a diatomic molecule that has a double covalent bond.
- Br_2
- I_2
- O_2
A: O_2

Q: Which element contains triple covalent bonds?
- oxygen
- nitrogen
- iodine
A: nitrogen

Q: What is the molecular shape of CO_2?
- linear
- bent
- trigonal planar
A: linear

Q: How many polar bonds does CH_4 contain?
- 0
- 2
- 4
A: 0

Q: Which molecule has only covalent bonds?
- CO_2
- Al_2O_3
- Mg_3N_2
A: CO_2

Q: Which compound has only ionic bonds?
- CO_2
- Al_2O_3
- H_2O_2
A: Al_2O_3

Q: The octet rule states that main group elements in the periodic table react to achieve a filled valence shell which consists of how many electrons?
- 2
- 4
- 8
A: 8

Q: What is the molecular shape and polarity for xenon tetrafluoride?
- square-planar and polar
- square-planar and non-polar
- tetrahedral and non-polar
A: square-planar and non-polar

Q: Which of the following elements are found in the p-block and can form an octet?
- He, P, S, As
- P, S, O, C
- He, Ar, Kr, Ne
A: P, S, O, C

Q: Based off molecular polarity determined by VSEPR theory, which of the following would be soluble in methanol?
- heptane
- ethanol
- pentane
A: ethanol

Q: Based off molecular polarity determined by VSEPR theory, which of the following would be insoluble in CCl_4?
- methanol
- octane
- hexane
A: methanol

Q: Based off molecular polarity determined by VSEPR theory, in which solvent would NaCl be the most soluble?
- CH_3OH
- CH_3CH_2OH
- H_2O
A: H_2O

Q: Based off molecular polarity determined by VSEPR theory, in which solvent would glucose be the least soluble?
- CH_3CH_2OCH_2CH_3
- CH_3OH
- H_2O
A: CH_3CH_2OCH_2CH_3

Q: Which statement best describes a bond forming between fluorine and iodine?
- fluorine and iodine are in the same group so the electron density in the bond is equaling shared giving rise to a non-polar bond
- fluorine is more electronegative than iodine so it will attract the electron density in the bond giving rise to a polar bond
- fluorine is less electronegative than iodine so it will attract the electron density in the bond giving rise to a polar bond
A: fluorine is more electronegative than iodine so it will attract the electron density in the bond giving rise to a polar bond

Q: Why are detergents and soaps good at cleaning up oily stains from dishes or clothing?
- Detergents and soaps work well to clean up oily messes because they are amphiphilic in nature so they contain both hydrophilic (polar) and hydrophobic (non-polar) ends. The hydrophobic end attaches to oils via hydrogen bonds creating micelles which leave the hydrophilic part exposed and can be washed away by water.
- Detergents and soaps work well to clean up oily messes because they are amphiphilic in nature so they contain both hydrophilic (non-polar) and hydrophobic (polar) ends. The hydrophobic end attaches to oils via London forces creating micelles which leave the hydrophilic part exposed and can be washed away by water.
- Detergents and soaps work well to clean up oily messes because they are amphiphilic in nature so they contain both hydrophilic (polar) and hydrophobic (non-polar) ends. The hydrophobic end attaches to oils via London forces creating micelles which leave the hydrophilic part exposed and can be washed away by water.
A: Detergents and soaps work well to clean up oily messes because they are amphiphilic in nature so they contain both hydrophilic (polar) and hydrophobic (non-polar) ends. The hydrophobic end attaches to oils via London forces creating micelles which leave the hydrophilic part exposed and can be washed away by water.

Q: Is it true that a molecule with polar bonds will always be polar?
- that is false, molecular polarity is determined by molecular shape
- that is true, molecular polarity is determined by bond polarity only
- that is false, molecular polarity is determined by electron group geometry
A: that is false, molecular polarity is determined by molecular shape

Q: An _____ reaction results when the energy required to break bonds in the reactants is greater than the energy released by the formation of products.
- exergonic
- endothermic
- exothermic
A: endothermic

Q: An _____ reaction results when the energy released by the formation of products is greater than the energy required to break the bonds in the reactants.
- exergonic
- endothermic
- exothermic
A: exothermic

Q: How many non-polar bonds does CH_3OH contain?
- 2
- 3
- 4
A: 3

Q: How many polar bonds does CCl_4 have in its structure?
- 0
- 2
- 4
A: 4