Question 1

Methane has a heat of fusion of 0.84 kJ/mol and a heat of vaporization of 9.2 kJ/mol.Estimate the value for the heat of sublimation.

Accepted Answer

The answer of Methane has a heat of fusion of...

Question 2

The mineral manganosite, manganese(II)oxide, crystallizes in the rock salt structure (the face-centered structure adopted by NaCl)with a density of 5.365 g/cm3.Find the unit cell edge length of manganosite.

Accepted Answer

A) 280.0 pm 
B) 352.8 pm 
C) 368.2 pm 
D) 417.9 pm 
E) 444.5 pm 
A) 280.0 pm 
B) 352.8 pm 
C) 368.2 pm 
D) 417.9 pm 
E) 444.5 pm

Question 3

BaCl2 crystallizes such that the Ba2+ ions are in a face-centered cubic arrangement and the Cl- ions are in the holes of the lattice (fluorite structure).How many Cl- ions are present in one unit cell of this crystal?

Accepted Answer

A) 1 
B) 2 
C) 4 
D) 6 
E) 8 
A) 1 
B) 2 
C) 4 
D) 6 
E) 8

Question 4

Suppose the atoms in a two-dimensional crystal have the following arrangement:   How many atoms are in one unit cell?

Accepted Answer

one (each corner of

Question 5

Glass is classified as which of the following?

Accepted Answer

A) metallic crystal. 
B) covalent solid. 
C) molecular crystal. 
D) amorphous solid. 
E) ionic crystal. 
A) metallic crystal. 
B) covalent solid. 
C) molecular crystal. 
D) amorphous solid. 
E) ionic crystal.

Question 6

Octane, C8H18, boils at 125°C as compared to water, which boils at 100°C.This information suggests that the dispersion forces in nonpolar octane molecules are stronger than dispersion forces and hydrogen bonding in water.

Accepted Answer

A) True 
 B)False

Question 7

Palladium crystallizes in a face-centered cubic unit cell.Its density is 12.0 g/cm3 at 27°C.Calculate the atomic radius of Pd.

Accepted Answer

A) 154 pm 
B) 138 pm 
C) 1.95 × 10-8 nm 
D) 0.109 nm 
E) 1.95 × 10-8 cm 
A) 154 pm 
B) 138 pm 
C) 1.95 × 10-8 nm 
D) 0.109 nm 
E) 1.95 × 10-8 cm

Question 8

Calculate the amount of heat needed to melt 2.00 kg of iron at its melting point (1,809 K), given that $\Delta$Hfus = 13.80 kJ/mol.

Accepted Answer

A) 27,600 J 
B) 27.6 kJ 
C) 494 kJ 
D) 25,000 kJ 
E) 27,600 kJ 
A) 27,600 J 
B) 27.6 kJ 
C) 494 kJ 
D) 25,000 kJ 
E) 27,600 kJ

Question 9

Which one of the following crystallizes in a metallic lattice?

Accepted Answer

A) C 
B) NaMnO4 
C) K 
D) LiClO4 
E) K2Cr2O7 
A) C 
B) NaMnO4 
C) K 
D) LiClO4 
E) K2Cr2O7

Question 10

Ethanol and dimethyl ether have the same molecular formula, C2H6O.Ethanol boils at 78.4°C.Dimethyl ether boils at -23.7°C.Their structural formulas are, respectively, CH3CH2OH and CH3OCH3.Explain why the boiling point of the ether is so much lower than the boiling point of ethanol.

Accepted Answer

Ethanol is a polar molecule th

Question 11

Octane is a liquid component of gasoline.Given the following vapor pressures of octane at various temperatures, estimate the boiling point of octane in Leadville, Colorado, where the atmospheric pressure is 496 mmHg. 400 mmHg @ 104°C, 500 mmHg @ 111°C, 600 mmHg @ 117°C, 700 mmHg @ 122°C, 760 mmHg @ 125°C

Accepted Answer

A) 125°C 
B) 120°C 
C) 115°C 
D) 110°C 
E) 105°C 
A) 125°C 
B) 120°C 
C) 115°C 
D) 110°C 
E) 105°C

Question 12

Which of following can form hydrogen bonds with water molecules? (1)Na+ (2)CH3COOH (3)C2H6 (4)CH3NH2

Accepted Answer

A) (1)and (2) 
B) (1)and (3) 
C) (2)and (3) 
D) (2)and (4) 
E) (3)and (4) 
A) (1)and (2) 
B) (1)and (3) 
C) (2)and (3) 
D) (2)and (4) 
E) (3)and (4)

Question 13

The molar enthalpy of vaporization of boron tribromide is 30.5 kJ/mol, and its normal boiling point is 91°C.What is the vapor pressure of BBr3 at 20°C?

Accepted Answer

A) 11.5 torr 
B) 311 torr 
C) 5.31 torr 
D) 143 torr 
E) 66.1 torr 
A) 11.5 torr 
B) 311 torr 
C) 5.31 torr 
D) 143 torr 
E) 66.1 torr

Question 14

Which of the following would be expected to have the lowest vapor pressure at room temperature?

Accepted Answer

A) ethanol, bp = 78°C 
B) methanol, bp = 65°C 
C) water, bp = 100°C 
D) acetone, bp = 56°C 
A) ethanol, bp = 78°C 
B) methanol, bp = 65°C 
C) water, bp = 100°C 
D) acetone, bp = 56°C

Question 15

W(s)is classified as which of the following?

Accepted Answer

A) metallic crystal. 
B) covalent solid. 
C) molecular crystal. 
D) amorphous solid. 
E) ionic crystal. 
A) metallic crystal. 
B) covalent solid. 
C) molecular crystal. 
D) amorphous solid. 
E) ionic crystal.

Question 16

Which is expected to have a higher vapor pressure, C8H18 or C4H10?

Accepted Answer

Question 17

The vapor pressure of ethanol is 400 mmHg at 63.5°C.Its molar heat of vaporization is 39.3 kJ/mol.What is vapor pressure of ethanol, in mmHg, at 34.9°C?

Accepted Answer

A) 0.0099 mmHg 
B) 4.61 mmHg 
C) 100 mmHg 
D) 200 mmHg 
E) 1,510 mmHg 
A) 0.0099 mmHg 
B) 4.61 mmHg 
C) 100 mmHg 
D) 200 mmHg 
E) 1,510 mmHg

Question 18

Indicate all the types of intermolecular forces of attraction in CHCl3(l).

Accepted Answer

dipole-dip

Question 19

Given that the heat of vaporization of mercury is 59.0 kJ/mol and the vapor pressure of mercury is 0.0017 torr at 25°C, calculate the normal boiling point of mercury.

Accepted Answer

380°C (the

Question 20

Indicate all the types of intermolecular forces of attraction in CH3OH(l).

Accepted Answer

hydrogen b

Exam 11: Intermolecular Forces and Liquids and Solids

Methane has a heat of fusion of 0.84 kJ/mol and a heat of vaporization of 9.2 kJ/mol.Estimate the value for the heat of sublimation.

The mineral manganosite, manganese(II)oxide, crystallizes in the rock salt structure (the face-centered structure adopted by NaCl)with a density of 5.365 g/cm3.Find the unit cell edge length of manganosite.

BaCl2 crystallizes such that the Ba2+ ions are in a face-centered cubic arrangement and the Cl- ions are in the holes of the lattice (fluorite structure).How many Cl- ions are present in one unit cell of this crystal?

Suppose the atoms in a two-dimensional crystal have the following arrangement: How many atoms are in one unit cell?

Glass is classified as which of the following?

Octane, C8H18, boils at 125°C as compared to water, which boils at 100°C.This information suggests that the dispersion forces in nonpolar octane molecules are stronger than dispersion forces and hydrogen bonding in water.

Palladium crystallizes in a face-centered cubic unit cell.Its density is 12.0 g/cm3 at 27°C.Calculate the atomic radius of Pd.

Calculate the amount of heat needed to melt 2.00 kg of iron at its melting point (1,809 K), given that Δ\DeltaΔ Hfus = 13.80 kJ/mol.

Which one of the following crystallizes in a metallic lattice?

Ethanol and dimethyl ether have the same molecular formula, C2H6O.Ethanol boils at 78.4°C.Dimethyl ether boils at -23.7°C.Their structural formulas are, respectively, CH3CH2OH and CH3OCH3.Explain why the boiling point of the ether is so much lower than the boiling point of ethanol.

Which of following can form hydrogen bonds with water molecules? (1)Na+ (2)CH3COOH (3)C2H6 (4)CH3NH2

The molar enthalpy of vaporization of boron tribromide is 30.5 kJ/mol, and its normal boiling point is 91°C.What is the vapor pressure of BBr3 at 20°C?

Which of the following would be expected to have the lowest vapor pressure at room temperature?

W(s)is classified as which of the following?

Which is expected to have a higher vapor pressure, C8H18 or C4H10?

The vapor pressure of ethanol is 400 mmHg at 63.5°C.Its molar heat of vaporization is 39.3 kJ/mol.What is vapor pressure of ethanol, in mmHg, at 34.9°C?

Indicate all the types of intermolecular forces of attraction in CHCl3(l).

Given that the heat of vaporization of mercury is 59.0 kJ/mol and the vapor pressure of mercury is 0.0017 torr at 25°C, calculate the normal boiling point of mercury.

Indicate all the types of intermolecular forces of attraction in CH3OH(l).

Chemistry: the Study of Change

Atoms, Molecules, and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Gases

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Periodic Relationships Among the Elements

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Acid-Base Equilibria and Solubility Equilibria

Entropy Free Energy and Equilibrium

Electrochemistry

Nuclear Chemistry

Chemistry in the Atmosphere

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Transition Metal Chemistry and Coordination Compounds

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The mineral manganosite, manganese(II)oxide, crystallizes in the rock salt structure (the face-centered structure adopted by NaCl)with a density of 5.365 g/cm³.Find the unit cell edge length of manganosite.

BaCl₂ crystallizes such that the Ba²⁺ ions are in a face-centered cubic arrangement and the Cl^- ions are in the holes of the lattice (fluorite structure).How many Cl^- ions are present in one unit cell of this crystal?

Octane, C₈H₁₈, boils at 125°C as compared to water, which boils at 100°C.This information suggests that the dispersion forces in nonpolar octane molecules are stronger than dispersion forces and hydrogen bonding in water.

Palladium crystallizes in a face-centered cubic unit cell.Its density is 12.0 g/cm³ at 27°C.Calculate the atomic radius of Pd.

Calculate the amount of heat needed to melt 2.00 kg of iron at its melting point (1,809 K), given that $\Delta$ H_fus = 13.80 kJ/mol.

Ethanol and dimethyl ether have the same molecular formula, C₂H₆O.Ethanol boils at 78.4°C.Dimethyl ether boils at -23.7°C.Their structural formulas are, respectively, CH₃CH₂OH and CH₃OCH₃.Explain why the boiling point of the ether is so much lower than the boiling point of ethanol.

Which of following can form hydrogen bonds with water molecules? (1)Na⁺ (2)CH₃COOH (3)C₂H₆ (4)CH₃NH₂

The molar enthalpy of vaporization of boron tribromide is 30.5 kJ/mol, and its normal boiling point is 91°C.What is the vapor pressure of BBr₃ at 20°C?

Which is expected to have a higher vapor pressure, C₈H₁₈ or C₄H₁₀?

Indicate all the types of intermolecular forces of attraction in CHCl₃(l).

Indicate all the types of intermolecular forces of attraction in CH₃OH(l).