Question

1. Would the following errors result in a higher or lower heat of neutralization? a. Student transferred 40,0 mL of HCI instead of 50.0 mL H b. Student used the temperature at 15 min. as final temperature instead of using the graph. Student used the specific heat of water, 4.184 J/g°C instead of the specific heat of C. the NaCl solution, 3.98 J/g°C. If the theoretical heat of neutralization for this reaction is 58 kJ/mol, what is the percent 2. error using your average heat of neutralization for your experiment?

50 ml HCL solution was added to 51 ml NaOH

Answer 1

• Heat of neutralization : If one equivalent of a base reacts with one equivalent of an acid and gives a salt and water, then the energy released is called enthalpy of neutralization or heat of neutralization There are three factors which affect the heat of meutralization is Amound of base and acid. ciis Acid and bare basicity. cili Acid and base strength. (a) It is given that, a student transfermed 40.0mL HCl unstead of 5000 ml. It means lomL HOI is less than the required amount. Here, total amount of acid is dess than the total amount of base and so complete neutralization reaction does not take place. As a result, there is no complete mentralization of bare occurs. Hence, head of mentralization will be less than the real value. (b) Given that the student used the temperature at 15 min. as last demperature instead of using graphe Since the demperodure is measured previous do the last equilibrium, the calculated value of heat of neutralization becomes fewer than the real value. It happen because the temperature difference is proportional to the heat of neutralization. Thus, in this case also heat of mentralization remains less than the actual value.

© Instead of specific heat of Naci Solution, Specific heat of water is used by the student. In this case, heat of neutralization becomes more than the actual value. Since the absorbed heat can be calculaded by the use of the heat capacity and also it is proportional to the heat capacity. Heat capacity of water is 4.104 J/gºc while heat capacity of Nall solution wis 3.90 J/goc. From the doda, cit us quite evident that the heat capacity of water is more than the heat Capacity of NaCl soledion. Therefore, heat of neutralization becomes more than the real value. ore than the headach of