A student mixed 25.0 ml of 1.50 M HCl and 25.0 ml of 1.50 M NaOH, both at 22.50 ºC, in a coffee cup calorimeter. The temperature of the mixture rose to 32.70 °C. Assume that the density of the resulting solution is 1.0 g/mL and the specific heat of the solution is 4.18 J/g°C.

(A) Balanced chemical equation for the reaction.

(B)Calculate the amount of heat absorbed by the resulting solution.

(C)How much heat is released by the reaction?

(D)Calculate ΔH for the reaction per mole of the base

NaOH_(aq) + HCl_(aq) → NaCl_(aq) + H2O_(l)

Amount of heat absorbed is 2,131.8J.

The amount of heat absorbed is equal to the amount of heat released since it is an exothermic reaction.

ΔH per mole =1,421.2J/mol

Step-by-step explanation

Sodium hydroxide reacts with hydrochloric acid in a neutralization reaction to for sodium chloride and water. The reaction is exothermic.

Heat energy is calculated by the formula Q=mC_pΔT, where Q is the heat variable, m is the mass of the object, C_p is the specific heat constant and ΔT is the temperature change.

Volume of the solution=25mL + 25mL

=50mL

Mass of the solution=Density x volume

=1 x 50

=50g

Heat energy, Q=mC_pΔT

=50 x 4.18 x (32.70-22.50)

=2,131.8J

This is an exothermic reaction hence the amount of heat absorbed is equal to the amount of heat released.

The mole ratio of reactants to products is 1:1:1

So the number of moles of NaCl is 1.5.

ΔH per mole=Total heat energy/number of moles

=2131.8/1.5

=1,421.2J/Mol

his is the molar heat of neutralization.