Question

looking for question 5, 6 7 and 8

5. In reaction 1, a student measured the temperature of the resultant solution when some NaOH pellets were still left in the calorimeter. How does it affect the value of AH reaction? 6. In reaction 2, a student forgot to put the lid back on the calorimeter after mixing NaOH pellet with HCl solution. How does it affect the value of AH reactiona? 7. In reaction 3, a student left the solution stirring for 30 min while talking to a friend. How does it affect the value of A Heractions ? 8. In this experiment, we assumed the density of water or any solution is 1.00 g/mL and that the specific heat capacity of any solution is 4.184 Jg="C) to simplify the calculation. List another assumption we made in this experiment. 6

Answer 1

5. $\Delta$ H reaction depends directly upon the temperature change of the reaction. If temperature change is high the value will be high and vice versa.

Now, dissolving NaOH is an exothermic process. Thus, temperature of solution increases. However, if all NaOH pellets are not dissolved, increase in temperature observed will be less. Thus, $\Delta$ H reaction value be low.

6. If the lid is not closed, the heat will move out of the calorimeter resulting isn lesser temperature cahnge. Thus, $\Delta$ H reaction value be low.

7. The process of stirring helps to coll down. If stirring will continue for 30mins, Tf will decrease. Thus, temperature change will be less resulting in $\Delta$ H reaction value to be low.