Question 1

If a chemical reaction occurs in a direction that has a positive change in entropy,then _____.

Accepted Answer

A)  the change in enthalpy must be negative. 
B)  the reaction must be spontaneous. 
C)  the heat goes from the system into the surroundings. 
D)  the reaction must be exothermic. 
E)  the disorder of the system increases. 
A)  the change in enthalpy must be negative. 
B)  the reaction must be spontaneous. 
C)  the heat goes from the system into the surroundings. 
D)  the reaction must be exothermic. 
E)  the disorder of the system increases.

Question 2

Determine ΔfG° at 298 K for SnO using the data below. Sn(s)+ SnO2(s)→ 2SnO(s)
Given: ΔrG° = 12.0 kJ/mol-rxn at 298K.
Substance
ΔfG°(kJ/mol)at 298 K
SnO(s)
?
SnO2(s)
-515.8

Accepted Answer

A)  -251.9 kJ/mol 
B)  -503.8 kJ/mol 
C)  527.8 kJ/mol 
D)  263.9 kJ/mol 
E)  1055.6 kJ/mol 
A)  -251.9 kJ/mol 
B)  -503.8 kJ/mol 
C)  527.8 kJ/mol 
D)  263.9 kJ/mol 
E)  1055.6 kJ/mol

Question 3

For a chemical system,ΔrG° and ΔrG are equal when:

Accepted Answer

A)  the system is in equilibrium. 
B)  the reactants and products are in standard state conditions. 
C)  the equilibrium constant,K,equals 0. 
D)  the reaction quotient,Q,is less than 1. 
E)  the reactants and products are in the gas phase. 
A)  the system is in equilibrium. 
B)  the reactants and products are in standard state conditions. 
C)  the equilibrium constant,K,equals 0. 
D)  the reaction quotient,Q,is less than 1. 
E)  the reactants and products are in the gas phase.

Question 4

At a temperature (in kelvin units)of _____,the entropy of a pure crystal is 0.0 J/K.

Accepted Answer

The answer of At a temperature (in kelvin units)of _____,the...

Question 5

Calculate ΔS°(universe)for the combustion of acetylene at 298.15 K using the reaction below.(Given: ΔS°(system)= -194.6 J/K and ΔH°(system)= -2511.2 kJ) 2 C2H2(g)+ 5 O2(g)→ 4 CO2(g)+ 2 H2O(g)

Accepted Answer

A)  -2453.2 J/K 
B)  -186.2 J/K 
C)  +186.2 J/K 
D)  +1290.4 J/K 
E)  +8228.0 J/K 
A)  -2453.2 J/K 
B)  -186.2 J/K 
C)  +186.2 J/K 
D)  +1290.4 J/K 
E)  +8228.0 J/K

Question 6

Calculate ΔG° at 298 K for the reaction below. I2(g)+ Br2(g)→ 2IBr(g)
Given: ΔrH° = -11.6 kJ/mol-rxn; ΔrS° = 12 J/K⋅mol-rxn at 298 K.

Accepted Answer

A)  -8.02 kJ/mol-rxn 
B)  15.2 kJ/mol-rxn 
C)  -15.2 kJ/mol-rxn 
D)  3.59 × 103 kJ/mol-rxn 
E)  -3.59 × 103 kJ/mol-rxn 
A)  -8.02 kJ/mol-rxn 
B)  15.2 kJ/mol-rxn 
C)  -15.2 kJ/mol-rxn 
D)  3.59 × 103 kJ/mol-rxn 
E)  -3.59 × 103 kJ/mol-rxn

If a chemical reaction occurs in a direction that has a positive change in entropy,then _____.

Determine Δ_fG° at 298 K for SnO using the data below. Sn(s)+ SnO₂(s)→ 2SnO(s) Given: Δ_rG° = 12.0 kJ/mol-rxn at 298K. Substance Δ_fG°(kJ/mol)at 298 K SnO(s) ? SnO₂(s) -515.8

For a chemical system,Δ_rG° and Δ_rG are equal when:

At a temperature (in kelvin units)of _____,the entropy of a pure crystal is 0.0 J/K.

Calculate ΔS°(universe)for the combustion of acetylene at 298.15 K using the reaction below.(Given: ΔS°(system)= -194.6 J/K and ΔH°(system)= -2511.2 kJ) 2 C₂H₂(g)+ 5 O₂(g)→ 4 CO₂(g)+ 2 H₂O(g)

Calculate ΔG° at 298 K for the reaction below. I₂(g)+ Br₂(g)→ 2IBr(g) Given: Δ_rH° = -11.6 kJ/mol-rxn; Δ_rS° = 12 J/K⋅mol-rxn at 298 K.

Basic Concepts of Chemistry

Lets Review: The Tools of Quantitative Chemistry

Atoms, molecules, and Ions

Chemical Reactions

Stoichiometry: Quantitative Information About Chemical Reactions

Principles of Chemical Reactivity: Energy and Chemical Reactions

The Structure of Atoms

The Structure of Atoms and Periodic Trends

Bonding and Molecular Structure

Bonding and Molecular Structure Orbital Hybridization and Molecular Orbitals

Gases and Their Properties

Intermolecular Forces and Liquids

The Solid State

Solutions and Their Behavior

Chemical Kinetics: the Rates of Chemical Reactions

Principles of Chemical Reactivity: Equilibria

Principles of Chemical Reactivity: the Chemistry of Acids and Bases

Principles of Chemical Reactivity: Other Aspects of Aqueous Equilibria

Principles of Chemical Reactivity: Electron Transfer Reactions

Environmental Chemistry: Earths Environment, energy, and Sustainability

The Chemistry of the Main Group Elements

The Chemistry of the Transition Elements

Carbon: Not Just Another Element

Biochemistry

Nuclear Chemistry

Filters

Exam 19: Principles of Chemical Reactivity: Entropy and Free Energy

If a chemical reaction occurs in a direction that has a positive change in entropy,then _____.

Determine ΔfG° at 298 K for SnO using the data below. Sn(s)+ SnO2(s)→ 2SnO(s) Given: ΔrG° = 12.0 kJ/mol-rxn at 298K. Substance ΔfG°(kJ/mol)at 298 K SnO(s) ? SnO2(s) -515.8

For a chemical system,ΔrG° and ΔrG are equal when:

At a temperature (in kelvin units)of _____,the entropy of a pure crystal is 0.0 J/K.

Calculate ΔS°(universe)for the combustion of acetylene at 298.15 K using the reaction below.(Given: ΔS°(system)= -194.6 J/K and ΔH°(system)= -2511.2 kJ) 2 C2H2(g)+ 5 O2(g)→ 4 CO2(g)+ 2 H2O(g)

Calculate ΔG° at 298 K for the reaction below. I2(g)+ Br2(g)→ 2IBr(g) Given: ΔrH° = -11.6 kJ/mol-rxn; ΔrS° = 12 J/K⋅mol-rxn at 298 K.

Basic Concepts of Chemistry

Lets Review: The Tools of Quantitative Chemistry

Atoms, molecules, and Ions

Chemical Reactions

Stoichiometry: Quantitative Information About Chemical Reactions

Principles of Chemical Reactivity: Energy and Chemical Reactions

The Structure of Atoms

The Structure of Atoms and Periodic Trends

Bonding and Molecular Structure

Bonding and Molecular Structure Orbital Hybridization and Molecular Orbitals

Gases and Their Properties

Intermolecular Forces and Liquids

The Solid State

Solutions and Their Behavior

Chemical Kinetics: the Rates of Chemical Reactions

Principles of Chemical Reactivity: Equilibria

Principles of Chemical Reactivity: the Chemistry of Acids and Bases

Principles of Chemical Reactivity: Other Aspects of Aqueous Equilibria

Principles of Chemical Reactivity: Electron Transfer Reactions

Environmental Chemistry: Earths Environment, energy, and Sustainability

The Chemistry of the Main Group Elements

The Chemistry of the Transition Elements

Carbon: Not Just Another Element

Biochemistry

Nuclear Chemistry

Filters

Determine Δ_fG° at 298 K for SnO using the data below. Sn(s)+ SnO₂(s)→ 2SnO(s) Given: Δ_rG° = 12.0 kJ/mol-rxn at 298K. Substance Δ_fG°(kJ/mol)at 298 K SnO(s) ? SnO₂(s) -515.8

For a chemical system,Δ_rG° and Δ_rG are equal when:

Calculate ΔS°(universe)for the combustion of acetylene at 298.15 K using the reaction below.(Given: ΔS°(system)= -194.6 J/K and ΔH°(system)= -2511.2 kJ) 2 C₂H₂(g)+ 5 O₂(g)→ 4 CO₂(g)+ 2 H₂O(g)

Calculate ΔG° at 298 K for the reaction below. I₂(g)+ Br₂(g)→ 2IBr(g) Given: Δ_rH° = -11.6 kJ/mol-rxn; Δ_rS° = 12 J/K⋅mol-rxn at 298 K.