Chemical Thermodynamics

In an adiabatic container, if a gas is compressed, its temperature will:

For a reaction involving only solids and liquids, the difference between $ΔH$ and $ΔU$ is usually:

The change in internal energy at constant volume is equal to:

Which of the following quantities is NOT a property of the system but depends on the process?

If $\Delta H$ is the enthalpy change and $\Delta U$ is the internal energy change, then for the reaction $2C(s) + 3H_{2}(g) \rightarrow C_{2}H_{6}(g)$, $\Delta H - \Delta U$ is equal to:

The unit of the product $P \Delta V$ in the SI system is:

In a reversible process, the system is always in ________ with the surroundings.

In an adiabatic process, the work done on the system is $500\text{ J}$. The internal energy of the system:

A system goes from state P to state Q via path I and returns to P via path II. If $q_{1}$ and $q_{2}$ are the heats absorbed in path I and II, and $w_{1}$ and $w_{2}$ are the works done by the system in path I and II respectively, then:

Which of the following processes has $w = 0$?

Which of the following defines the standard enthalpy of reaction?

The heat capacity at constant pressure ($C_p$) is _______ than the heat capacity at constant volume ($C_v$) for an ideal gas.

What is the change in enthalpy ($\\Delta H$) for a cyclic process?

Which of the following is an extensive property?

The thermodynamic cycle for the dissolution of sodium chloride is shown below. According to Hess's Law, the enthalpy of solution ($H1$) can be calculated from the lattice enthalpy ($H2$) and the total hydration enthalpy ($H3$). If the lattice enthalpy of $NaCl(s)$ is $+788\ kJ\ mol^{-1}$ and the total hydration enthalpy of its gaseous ions is $-784\ kJ\ mol^{-1}$, what is the value of the enthalpy of solution ($H1$)?

Calculate $\Delta H$ for the reaction $2C_{(s)} + 3H_{2(g)} \rightarrow C_2H_{6(g)}$ if the enthalpies of combustion of $C(s)$, $H_2(g)$, and $C_2H_6(g)$ are $-394$, $-286$, and $-1560\ kJ/mol$ respectively.

The enthalpy of combustion of $C(graphite)$ to $CO_2(g)$ is $-393.5\ kJ/mol$. What is the enthalpy of formation of $CO_2(g)$?

Using the bond enthalpies: $C-H = 414$, $Cl-Cl = 243$, $C-Cl = 331$, $H-Cl = 431$ (all in $kJ/mol$), calculate $\Delta H$ for the reaction: $CH_{4(g)} + Cl_{2(g)} \rightarrow CH_3Cl_{(g)} + HCl_{(g)}$.

At $298\ K$, the standard enthalpies of formation of $NO_{2(g)}$ and $N_2O_{4(g)}$ are $33.2\ kJ/mol$ and $9.16\ kJ/mol$ respectively. Calculate the enthalpy of dimerization of $NO_2$.

The enthalpy of neutralization of $HCl$ by $NaOH$ is $-57.3\ kJ$ and $NH_4OH$ by $HCl$ is $-51.3\ kJ$. The enthalpy of dissociation of $NH_4OH$ is:

For a reaction involving only solids and liquids, the difference between $\Delta G$ at constant pressure and $\Delta A$ (Helmholtz free energy) at constant volume is usually:

In the Gibbs equation, if $\Delta S$ is positive, how does the term $-T\Delta S$ behave as temperature increases?

Which of the following is NOT a state function?

If $\Delta G$ for a reaction is $+50 \text{ kJ/mol}$, the reaction is:

Which of the following describes the 'driving force' of a reaction that is spontaneous only at very high temperatures?

What is the value of $\\Delta G$ when a system reaches a state of chemical equilibrium at constant temperature and pressure?

A reaction has $\\Delta H = +100\\text{ kJ}$ and $\\Delta S = -50\\text{ J/K}$. This reaction is:

If $\Delta G^\circ$ for a reaction is $-100\text{ kJ/mol}$ at $300\text{ K}$, what is the value of $\ln K$?

For a reaction where $\Delta H = T\Delta S$, which of the following must be true?

In the reaction $A(s) \rightarrow A(g)$, the enthalpy of sublimation is $200\text{ kJ/mol}$ and $\Delta S = 250\text{ J/K/mol}$. At $1000\text{ K}$, the process is:

Hess's Law is valid for reactions occurring at standard state. Standard state pressure is usually defined as:

If $\\Delta H$ for a reaction is positive, the reaction is classified as:

Hess's Law allows us to treat thermochemical equations like:

Given: (1) $H_2(g) + Cl_2(g) \\rightarrow 2HCl(g)$, $\\Delta H = -184$ kJ. What is the enthalpy of formation of $HCl(g)$?

Using the cycle shown, if the enthalpy change for $X \rightarrow Z$ is $+50$ kJ and for $Y \rightarrow Z$ is $+20$ kJ, what is the enthalpy change for $X \rightarrow Y$?

Determine the enthalpy of formation of $PCl_5$ from its elements given the following:

1. $P_4(s) + 6Cl_2(g) \rightarrow 4PCl_3(l)$; $\Delta H = -1280$ kJ
2. $PCl_3(l) + Cl_2(g) \rightarrow PCl_5(s)$; $\Delta H = -124$ kJ

Hess's Law states that the heat change in a reaction is the same whether it takes place in one step or several. This is based on the fact that enthalpy ($H$) depends only on:

Calculate the enthalpy of formation of $Ca(OH)_2(s)$ from the following: $CaO(s) + H_2O(l) \rightarrow Ca(OH)_2(s); \Delta H = -65.2$ kJ $\Delta H_f [CaO(s)] = -635.1$ kJ/mol $\Delta H_f [H_2O(l)] = -285.8$ kJ/mol

Determine the bond enthalpy of $S-F$ in $SF_6$ using: $\Delta H_f [SF_6(g)] = -1209$ kJ/mol $\Delta H_{atomization} [S(s)] = 278$ kJ/mol Bond energy of $F-F = 159$ kJ/mol

Calculate the enthalpy of formation of acetic acid ($CH_3COOH$) given: $\Delta H_{combustion}$ of $CH_3COOH(l) = -871$ kJ/mol $\Delta H_f$ of $CO_2(g) = -394$ kJ/mol $\Delta H_f$ of $H_2O(l) = -286$ kJ/mol