Question

A 100.0-mL sample of 1.00 M NaOH is mixed with 50.0 mL of 1.00 M H2SO4 in a large Styrofoam coffee cup calorimeter fitted with a lid through which a thermometer passes. The acid-base reaction is as follows:

2 NaOH(aq) + H2SO4(aq) → Na2SO4(aq) + 2 H2O(l)
The temperature of each solution before mixing is 22.3 °C. After mixing, the temperature of the solution mixture reaches a maximum temperature of 31.4 °C. Assume the density of the solution mixture is 1.00 g/mL, its specific heat is 4.18 J/g.°C, and no heat is lost to the surroundings. Calculate the enthalpy change, in kj, per mole of H2SO4 in the reaction.
a. +85.6 kJ/mol.
b. -85.6 kJ/mol.
c. +5.71 kJ/mol.
d. -5.71 kJ/mol.
e. -114 kJ/mol.

Answer 1

To calculate the enthalpy change per mole of H2SO4 in the reaction, we need to calculate the heat gained by the solution and then divide it by the number of moles of H2SO4.

Step-by-step explanation:

In this acid-base reaction, a 100.0 mL sample of 1.00 M NaOH and 50.0 mL of 1.00 M H2SO4 are mixed in a calorimeter. The temperature of the mixture increases from 22.3 °C to 31.4 °C. To calculate the enthalpy change per mole of H2SO4, we need to use the equation q = mcΔT.

The heat gained by the solution can be calculated using the mass of the solution, its specific heat, and the change in temperature. Then, we can divide this heat by the number of moles of H2SO4 to find the enthalpy change per mole of H2SO4.