In the space provided below, write the balanced net ionic reaction equations for
ID: 528809 • Letter: I
Question
In the space provided below, write the balanced net ionic reaction equations for each described reaction. Use the table of thermodynamic data in your textbook (or another approved resource) to calculate the molar enthalpy of the reactions. (Neatly show how you obtained your result) Reaction 1: Reaction between 2.00 M HCI and 2.00 M NaOH aqueous solutions: Reaction 2: Reaction between 2.00 M NaOH and 2.00 M NH_4 Cl aqueous solutions Reaction 3: Reaction between 2.00 M HCI and 2.00 M NH_3 (=NH_4 OH) aqueous solutionsExplanation / Answer
1. The net reaction is: NaOH + HCl = NaCl + H2O
NaOH dissociates as : NaOH = Na+ + OH-
HCl dissociates as: HCl = H+ + Cl-
The net ionic reaction is: Na+ + OH- + H+ + Cl- = Na+ + Cl- + H2O
It is a neutralisation reaction between strong acid and strong base and standard enthalpy change for the neutralisation (dH) = -55.8 KJ/ mol
2.Net reaction between NaOH and NH4Cl: NaOH + NH4Cl = NaCl + NH3 + H2O
The net ionic reaction is: Na+ + OH- + NH4+ + Cl- = Na+ + Cl- + NH3 + H2O
Enthalpy change of the reaction is +30.56 KJ/ mol and it is an endothermic reaction.
3. The net reaction is: HCl + NH4OH = NH4Cl + H2O
HCl dissociates as: HCl = H+ + Cl-
NH4OH dissociates as: NH4+ + OH-
The net ion balanced reaction is : H+ + Cl- + NH4+ + OH- = NH4+ + Cl- + H2O
It is a neutralisation reaction between strong acid and weak base and the enthalpy change for the reaction is less than that of strong acid and strong base because weak base dissociates weakly and full acid is not required for the neutralisation. The value is - 51.5 KJ/mol