A common laboratory reaction is the neutralization of an acid with a base. When 50.0 mL of 0.500 M HCl at 25.0$\degree$C is added to 50.0 mL of 0.500 M NaOH at 25.0$\degree$C in a coffee cup calorimeter, the temperature of the mixture rises to 28.2$\degree$C. What is the heat of reaction per mole of acid? Assume the mixture has a specific heat capacity of 4.18 J/(g ? K) and that the densities of the reactant solutions are both 1.00 g/mL.

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The heat of reaction is given by the equation:$$q = mC_p\Delta T$$where:* q is the heat of reaction* m is the mass of the solution* C_p is the specific heat capacity of the solution* \Delta T is the change in temperatureIn this case, the mass of the solution is:$$m = (50.0 mL + 50.0 mL) 	imes 1.00 g/mL = 100.0 g$$The specific heat capacity of the solution is:$$C_p = 4.18 J/(g ? K)$$The change in temperature is:$$\Delta T = 28.2\degree C - 25.0\degree C = 3.2\degree C$$Substituting these values into the equation, we get:$$q = (100.0 g) 	imes (4.18 J/(g ? K)) 	imes (3.2\degree C) = 1340.8 J$$The heat of reaction per mole of acid is:$$\frac{1340.8 J}{0.0500 mol} = 26816 J/mol$$Therefore, the correct answer is D) 54 kJ.

A Common Laboratory Reaction Is the Neutralization of an Acid °\degree°

A Common Laboratory Reaction Is the Neutralization of an Acid $\degree$