Producer gas (carbon monoxide) is prepared by passing air over red-hot coke:

$$\mathrm{C}(\mathrm{s})+\frac{1}{2} \mathrm{O}_2(\mathrm{~g}) \longrightarrow \mathrm{CO}(\mathrm{g})$$

Water gas (a mixture of carbon monoxide and hydrogen) is prepared by passing steam over redhot coke:

$$\mathrm{C}(\mathrm{s})+\mathrm{H}_2 \mathrm{O}(\mathrm{g}) \longrightarrow \mathrm{CO}(\mathrm{g})+\mathrm{H}_2(\mathrm{~g})$$

For many years, both producer gas and water gas were used as fuels in industry and for domestic cooking. The large-scale preparation of these gases was carried out alternately, that is, first producer gas, then water gas, and so on. Using thermochemical reasoning, explain why this procedure was chosen.

The combustion of what volume of ethane $\left(\mathrm{C}_2 \mathrm{H}_6\right)$, measured at $23.0^{\circ} \mathrm{C}$ and $752 \mathrm{~mm} \mathrm{Hg}$, would be required to heat $855 \mathrm{~g}$ of water from $25.0^{\circ} \mathrm{C}$ to $98.0^{\circ} \mathrm{C}$ ?

Calculate the work done (in joules) when 1.0 mole of water vaporizes at 1.0 atm and 100$\degree$C. Assume ideal gas behavior and that the volume of liquid water is negligible compared with that of steam at 100$\degree$C.

The heat of fusion of ice at the standard melting point $\left(0^{\circ} \mathrm{C}\right)$ is $6.01 \mathrm{~kJ} \mathrm{~mol}^{-1}$. Determine the heat of fusion at $-10^{\circ} \mathrm{C}$ using data from Appendix 2.

The enthalpy of vaporization is found to decrease with increasing temperature for a certain substance. What information does this give you about the relative properties of the liquid and vapor phases?

The molar enthalpies of fusion and vaporization of water at $298 \mathrm{~K}$ are $6.01$ and $44.01 \mathrm{~kJ} \mathrm{~mol}^{-1}$, respectively. Use these values to estimate the molar enthalpy of sublimation of ice.

The molar enthalpies of fusion and sublimation of molecular iodine are $15.27$ and $62.30 \mathrm{~kJ} \mathrm{~mol}^{-1}$, respectively. Estimate the molar heat of vaporization of liquid iodine.

How much heat (in kJ) is needed to convert $866 \mathrm{~g}$ of ice at $-10^{\circ} \mathrm{C}$ to steam at $126^{\circ} \mathrm{C}$ ? (The specific heat capacities of ice and steam are $2.03$ and $1.99 \mathrm{~J} \mathrm{~g}^{-1}$ ${ }^{\circ} \mathrm{C}^{-1}$, respectively.)

Calculate the amount of heat (in $\mathrm{kJ}$ ) required to convert $74.6 \mathrm{~g}$ of water to steam at $100^{\circ} \mathrm{C}$.

Calculate the work done when $50.0 \mathrm{~g}$ of tin dissolves in excess acid at $1.00$ bar and $25^{\circ} \mathrm{C}$

$$\mathrm{Sn}(s)+2 \mathrm{H}^{+}(a q) \longrightarrow \mathrm{Sn}^{2+}(a q)+\mathrm{H}_2(\mathrm{~g})$$

Assume ideal gas behavior.

Use the bond enthalpy values in Table $7.6$ to calculate the enthalpy of combustion for ethane $\left(\mathrm{C}_2 \mathrm{H}_6\right)$ :

$$\mathrm{C}_2 \mathrm{H}_6(\mathrm{~g})+\frac{7}{2} \mathrm{O}_2(g) \longrightarrow 2 \mathrm{CO}_2(g)+3 \mathrm{H}_2 \mathrm{O}(g)$$

Use the bond enthalpy data in Table $7.6$ to calculate the enthalpies of formation of the following gases:
$\mathrm{H}_2 \mathrm{NCl}$.

Use the bond enthalpy data in Table $7.6$ to calculate the enthalpies of formation of the following gases:
$\mathrm{H}_2 \mathrm{O}_2$.

Use the bond enthalpy data in Table $7.6$ to calculate the enthalpies of formation of the following gases:
$\mathrm{NH}_3$.