General Chemistry Answers

For a certain process at 127°C, ΔG = -16.20 kJ and ΔH = -17.0 kJ. What is the entropy change for this process at this temperature? Express your answer in the form, ΔS = ____________________ J/K.

Calculate ΔG⁰ at 298 K for the reaction below.

Fe₂O₃(s) + 13CO(g) > 2Fe(CO)₅(g) + 3CO₂(g)

ΔH⁰_f (kJ/mol) -824.2 -110.5 -733.8 -393.5

S⁰ (J/mol•K) 87.4 197.6 445.2 213.6

Calculate the ΔG⁰_f at 298 K for the PbCI₂(s) from the following information. ΔG⁰ for the reactions below is -58.4 kJ at 298 K.

PbS(s) + 2HCI(g) > PbCI₂(s) + H₂S(g)

ΔG⁰_f (kJ/mol) 97.82 149.0 0 -228.6

Calculate the Standard Gibbs free energy change for the following reaction at 25 degree celcius.

CaCO₃ + 2HCI(g) > CaCI₂(s) + CO₂(g) + H₂O(I)

ΔG⁰_f (kJ/mol) 1129 -95.3 -750.2 -394.4 -237.2

Solve the following problems.

1. A voltaic cell is based on a Co2+ /Co half-cell and an AgCl/Ag half-cell.

a. What reaction occurs at the anode?

b. What is the standard cell potential?

2. Using the standard reduction potentials, calculate the standard emf for each of the following reactions:

a. 2Al3+ + 3Cd ⟶ 2Al + 3Cd2+

b. Cr + 2Cr3+⟶3Cr2+

c. H2 + I2 ⟶ 2H+ + 2I

Determine if each of the following redox reactions is spontaneous or not.

1. Cu + 2Ag+ ⟶ Cu2+ + 2Ag

2. Al3+ + Fe ⟶ Al + Fe2+

3. Zn + Ni2+ ⟶ Zn2+ + Ni

4. 3Pb + 2Au3+ ⟶ 3Pb2+ + 2Au

5. Hg + Pb2+⟶ Hg2+ + Pb

Determine if each of the following redox reactions is spontaneous or not.

1. Cu + 2Ag+ ⟶ Cu2+ + 2Ag

2. Al3+ + Fe ⟶ Al + Fe2+

3. Zn + Ni2+ ⟶ Zn2+ + Ni

4. 3Pb + 2Au3+ ⟶ 3Pb2+ + 2Au

5. Hg + Pb2+⟶ Hg2+ + Pb

AH-453 kJ/mol-rxn P4010(S) + 6H₂O(1)-4H3PO4(aq) How many grams of P4010(S) would have to react to produce 167 kJ of energy?

The metals in Group IIIA, IVA and VA of the periodic table are not transition metals. However, all but 1 have variable charges. What element in Group IIIA, Period 3 has a fixed charge, and what is that charge?

How can you separate a mixture of salt, sand and water, stating the technique or principle of the separation?