Question

5. Compare the definition of a weak acid to the definition of a strong acid to explain why the reaction of acetic acid(HC2H3O2) (a weak acid)) with NaoH(a strong base) is less exothermic than the reaction between HCl(a strong acid) and NaoH.
6. A student carries out a calorimetry experiment using HCI and NaoH. What effect will each of the following have on the calculated enthalpy of the reaction relative to the actual enthalpy of reaction? (larger, smaller or no change). Explain your reasoning. a. The thermometer always registered a temperature 0.30 oc higher than the actual temperature b. The calorimeter constant used in the calculations by the student is larger than the actual value. (Hint: The best way to answer this question is to take your calorimeter constant, add at least 5 or 10 to the value and quickly redo the calculations. After completing the calculations, you should be able to complete the following statement: As the calorimeter constant increases, the calculated enthalpy of the reaction c. Unfortunately, the HCI concentration was actually 1.90 M instead of the 2.00 M HCI used in the calculations. (Hint: do a similar calculation. This is an estimate of how errors affect the result. If your data is not matching the expected values, perhaps these questions will help you understand why.)

Answer 1

5.

An acid that dissociates incompletely(partially) into its ionic species in its aqueous solution is called weak acid.

An acid that dissociates completely into itsionic species in its aqueous solution is caled strong acid.

The reaction is exothermic when the more bonds formed.

Since strong acid dissociates completely, more number of H⁺ ions produced that reacts with OH^- ions from the base to form water.

Since weak acid dissociates partially, it produces less number of H⁺ ion than strong acid, so, the bonds formed oin the case of weak acid strong base is less than that of strong acid and strong base.

So, more energy released in the case of strong acid and strong base than that of weak acid and strong base.

Therefore, the reaction between weak acid and strong acid is less exothermic than the reaction between strong acid and strong base.