A 10.00 mL aliquot of 0.100 M NaOH is added to 15.00 mL of 0.100M HCl in a coffee cup calorimeter. The initial temperature of the two dilute liquids were both 25.0 degrees C and the final temperature of the mixture was found to be 37.8 degrees C. What is the (molar) heat of reaction for the neutralization?
To find the molar heat of reaction for the neutralization, you need to first calculate the heat exchanged during the reaction using the formula:
q = m * c * ΔT
where:
- q is the heat exchanged (in Joules),
- m is the mass of the solution (in grams),
- c is the specific heat capacity of the solution (in J/g°C), and
- ΔT is the change in temperature (in °C).
In this case, you have 10.00 mL of 0.100 M NaOH and 15.00 mL of 0.100 M HCl. These volumes need to be converted to mass using the density and molarity of the solutions.
1. Calculate the mass of NaOH:
- Convert 10.00 mL to grams using the density of NaOH solution.
- Use the molarity of NaOH to find the moles of NaOH.
- Calculate the mass of NaOH using the molar mass of NaOH.
2. Calculate the mass of HCl:
- Convert 15.00 mL to grams using the density of HCl solution.
- Use the molarity of HCl to find the moles of HCl.
- Calculate the mass of HCl using the molar mass of HCl.
3. Calculate the total mass of the solution by adding the masses of NaOH and HCl.
4. Calculate the heat exchanged during the reaction using the formula mentioned earlier, where:
- ΔT is the difference between the final temperature and the initial temperature.
5. To find the molar heat of reaction, divide the heat exchanged (q) by the number of moles of the limiting reactant. In this case, the limiting reactant is the reactant with the fewest moles.
Note: It's important to make sure all units are consistent throughout the calculations, such as converting volumes to the same units and using the appropriate molar masses and densities.
Once you have completed these steps, you will be able to determine the molar heat of reaction for the neutralization.