Measure Delta H for the reaction that occurs when 100 mL of reagent A (0.1 M) is combined with 100mL of regent B (0.1 M). When the two are combined the temperature is 25.0*C. You may assume the heat capacity of the aqueous solutions is equal to the heat capacity of water 4.18 J/g K.
With the available data it is impossible to solve this problem! Please check the explanation below in order to know how to solve it
In this sense you are missing information about the initial temperature of the solutions or the temperature change, since the energy released during the reaction is calculated as:
H = m * Ce * (Tf - To)
where m stands for the mass of the total solution (200 g considering that you are mixing 100 mL of two different acqueous solutions and that water has a density of 1g/ml). Ce stands for the heat capacity of water (4.18 J / g ºC). And To and Tf stands for the initial and final temperatures, respectively.
Since you are missing the information about To it is impossible to arrive to the answer. To do so, you should substitute it in the formula:
H = 2004.18(25-To) = 836*(25-To)