Question

Determining the heat of reactions in aqueous solution

The stockroom of the virtual laboratory contains a cabinet called "Thermochemistry Solutions "Different concentrations of Reagent A and Reagent 8 have been piaced into this cabinet. You will use these solutions to answer the questions below.

1. Use the lab to measure Delta Hº for the reaction that occurs when reagents A and B are combined:
A+B<+=>C
Please note that each prepared flask contains 100 mL of solution Also, you may assume the heat capacity of the aqueous solutions is equal to the heat capacity of water 4.18 J/gKº
2. Using water and the reagents provided in the lab create two solutions such that when you mix equal amounts together the resulting solution has an initial temperature of 50° C
Please describe your complete procedure and the key quantities you measured Points are based upon your final answer and whether or not you explain your procedure in sufficient detail for us to reproduce your actions You are not graded on the method you used ali approaches that meet the above goal are equally valid

Answer 1

Calorimetry is a method to determine the heat of a reaction (ΔH) by measuring temperature changes in a constant-pressure environment, taking into account the mass and specific heat capacity of the aqueous solution.

Step-by-step explanation:

The heat of reaction, or enthalpy change (ΔH), in an aqueous solution can be determined through calorimetry, which involves measuring temperature changes in a chemical reaction to calculate the heat absorbed or released. For example, the reaction between NaOH and HCl in an aqueous solution results in a temperature increase, indicating an exothermic reaction. By using the specific heat capacity of water (4.18 J/g°C) and the mass of the solution, one can calculate the heat (q) using the formula q = m⋅c⋅ΔT, where m is the mass of the solution, c is the specific heat capacity, and ΔT is the change in temperature.

To carry out a constant-pressure calorimetry experiment, one must ensure no heat is lost to the surroundings or absorbed by the calorimeter itself. By mixing known quantities of different reagents at known temperatures and measuring the temperature change when the reaction occurs, we can determine the enthalpy change for the reaction. The conditions must be such that the resulting solution reaches thermal equilibrium, where the net heat change equals zero, indicating all of the heat released by the reaction has been absorbed by the solution.