To determine the molar enthalpy of neutralization of nitric acid ($\Delta H_{\text{neut}}$), we can use the data from the calorimetry experiment. The following steps outline the process:

1. Determine the heat absorbed or released by the solution ($q$): The heat change $q$ can be calculated using the formula: $q = m \cdot c \cdot \Delta T$ where:

   • $m$ is the mass of the solution (in grams)
   • $c$ is the specific heat capacity of the solution (assumed to be the same as water, $4.18 \, \text{J/g}^\circ\text{C}$)
   • $\Delta T$ is the change in temperature ($T_{\text{final}} - T_{\text{initial}}$)

2. Calculate the total volume and mass of the solution: Assuming the density of the solutions is approximately $1.00 \, \text{g/mL}$: $\text{Total volume} = 61.1 \, \text{mL} + 78.0 \, \text{mL} = 139.1 \, \text{mL}$ $\text{Total mass} = 139.1 \, \text{g}$

3. Calculate the change in temperature: $\Delta T = 29.00^\circ\text{C} - 22.90^\circ\text{C} = 6.10^\circ\text{C}$

4. Calculate the heat change ($q$): $q = 139.1 \, \text{g} \times 4.18 \, \text{J/g}^\circ\text{C} \times 6.10^\circ\text{C}$ $q \approx 3544.89 \, \text{J}$ Since $1 \, \text{kJ} = 1000 \, \text{J}$, we convert $q$ to kJ: $q \approx 3.54489 \, \text{kJ}$

5. Determine the number of moles of $\text{HNO}_3$ reacted: $\text{Number of moles of } \text{HNO}_3 = 61.1 \, \text{mL} \times \frac{1.00 \, \text{mol}}{1000 \, \text{mL}} = 0.0611 \, \text{mol}$

6. Calculate the molar enthalpy of neutralization ($\Delta H_{\text{neut}}$): $\Delta H_{\text{neut}} = \frac{q}{\text{moles of } \text{HNO}_3}$ $\Delta H_{\text{neut}} = \frac{3.54489 \, \text{kJ}}{0.0611 \, \text{mol}} \approx 58.03 \, \text{kJ/mol}$

So, the molar enthalpy of neutralization of nitric acid is approximately $\boxed{58.03} \, \text{kJ/mol}$.

Would you like further details or have any questions?

Here are 5 questions you might want to ask:

1. How do you convert temperature changes to heat energy in calorimetry?
2. What assumptions are made in calorimetry calculations?
3. How does specific heat capacity affect the heat change in a solution?
4. Can you explain the steps to balance a neutralization reaction equation?
5. What are some common sources of error in calorimetry experiments?

Tip: When performing calorimetry experiments, ensure that the calorimeter is well-insulated to minimize heat exchange with the surroundings for more accurate measurements.