Question

1. (14 pts.)  Write the balanced chemical equation for the chemical

reaction that makes up part of the thermochemical equation involving the DH_f^o for monochloroamine gas, NH₂Cl.

                        

Using appropriate bond energies, find DH_f^o, in kJ/mol, for monochloroamine.

2. (12 pts.)  A 2.490-g sample of cadmium metal completely reacts

   when placed in a coffee cup calorimeter that contains 75.0 mL of a

dilute sulfuric acid solution (aqueous) (density of 1.03 g/mL) to produce hydrogen gas and dissolved cadmium sulfate.  The chemical reaction is exothermic causing the temperature of the resulting aqueous solution to change from 21.5^oC to 32.5^oC.  

1. Write a balanced chemical equation for the chemical reaction that occurs.

2. Find the enthalpy change, in kJ/mol, for the chemical reaction, assuming the specific heat of the resulting aqueous solution is

4.18 J/(g×C^o) and assuming the coffee cup calorimeter is not involved in any heat exchange.

Page 3

3. (14 pts.)  An important process in industry is the conversion of

   iron(III) oxide to iron metal as represented by the balanced

   chemical equation given below.

                  Fe₂O₃(s) + 3COg) ® 2Fe(s) + 3CO₂(g)

1. Using appropriate thermodynamic data, find ∆H^o_reaction.

2. Using appropriate thermodynamic data, find ∆S^o_reaction.

3. Using appropriate thermodynamic data, find ∆G^o_reaction.

4. Comment on the spontaneity of the chemical reaction, using

  appropriate thermodynamic terms.

1. (14 pts.)  Write the balanced chemical equation for the chemical

reaction that makes up part of the thermochemical equation involving the DH_f^o for monochloroamine gas, NH₂Cl.

                        

Using appropriate bond energies, find DH_f^o, in kJ/mol, for monochloroamine.

2. (12 pts.)  A 2.490-g sample of cadmium metal completely reacts

   when placed in a coffee cup calorimeter that contains 75.0 mL of a

dilute sulfuric acid solution (aqueous) (density of 1.03 g/mL) to produce hydrogen gas and dissolved cadmium sulfate.  The chemical reaction is exothermic causing the temperature of the resulting aqueous solution to change from 21.5^oC to 32.5^oC.  

1. Write a balanced chemical equation for the chemical reaction that occurs.

2. Find the enthalpy change, in kJ/mol, for the chemical reaction, assuming the specific heat of the resulting aqueous solution is

4.18 J/(g×C^o) and assuming the coffee cup calorimeter is not involved in any heat exchange.

Page 3

3. (14 pts.)  An important process in industry is the conversion of

   iron(III) oxide to iron metal as represented by the balanced

   chemical equation given below.

                  Fe₂O₃(s) + 3COg) ® 2Fe(s) + 3CO₂(g)

1. Using appropriate thermodynamic data, find ∆H^o_reaction.

2. Using appropriate thermodynamic data, find ∆S^o_reaction.

3. Using appropriate thermodynamic data, find ∆G^o_reaction.

4. Comment on the spontaneity of the chemical reaction, using

  appropriate thermodynamic terms.

Answer 1

4 1 1 2 + H₂ + Cl₂ → NH CI NEN HH CI-CI H-N-C1 H 12 BH f = (BE) Read - (B.E.) pod. -Bwand) + Duu + (Delci) - ben-u) ton-eil] – qus + 436 + 242 - [ 21340)+142] T oH f = 5515 kJ/mol This enthalpy of formation of Mittel (chloramine) was found to be 55.5 ksimal