The pH of a solution was found by measuring the emf of a cell
composed of a standard silver electrode and a hydrogen electrode of
unknown hydrogen ion concentration. If the emf was 1.01v when the
pressure of hydrogen was 1.00atm, what was the pH at
25oC?
Calculate the cell potential and the equilibrium constant for
the following reaction at 298 K: Co2+(aq) + 2I-(aq) Co(s) + I2(s)
Hint: Carry at least 5 significant figures during intermediate
calculations to avoid round off error when taking the
antilogarithm. Equilibrium constant:
Calculate the cell potential and the equilibrium constant for
the following reaction at 298 K:
I2(s) +
Hg(l) =
2I-(aq)
+ Hg2+(aq)
Hint: Carry at least 5 significant figures during intermediate
calculations to avoid round off error when taking the
antilogarithm.
Equilibrium constant: -------
Calculate the equilibrium constant at 298 K for the reaction of
ammonia with oxygen to form nitrogen and water. The data refer to
298 K.
4NH3(g) + 3O2(g) <> 2N2(g) + 6H2O(l)
Substance NH3(g) O2(g) N2(g) H2O(l)
ΔH°f (kJ/mol) -46 0 0 -285
ΔG°f (kJ/mol) -16 0 0 -237
S°(J/K·mol) 192 205 192 70
I thought Kc is just Molar concentration of Products divide by
Molar concentration on Reactants which would be 12 x
16 divide by 14 x 13...
Calculate ΔrG○ at 298 K for these reactions and predict the
effect on ΔrG○ of lowering the temperature: a. NH3 (g) + HBr (g) →
NH4Br (s) b. CaCO3 (s) → CaO (s) + CO2 (g) c. CH4 (g) + 3 Cl2 (g) →
CHCl3 (g) + 3 HCl (g) (ΔfG○ for CHCl3 (g) is -70.4 kJ/mol)
Use data from Appendix C to calculate the equilibrium constant,
K, and ΔG∘ at 298 K for each of the following
reactions.
H2(g)+I2(g)⇌2HI(g)
Calculate ΔG∘.
Express your answer to four significant figures and include the
appropriate units.
Part A
H2(g)+I2(g)⇌2HI(g)
Calculate ΔG∘.
Express your answer to four significant figures and include the
appropriate units.
Part B
Calculate the equilibrium constant, K.
Express your answer using two significant figures.
Part C
C2H5OH(g)⇌C2H4(g)+H2O(g)
Calculate ΔG∘.
Express your answer to two significant figures...
The density of a 0.438 M solution of potassium chromate (K2CrO4)
at 298 K is 1.063 g/mL. a.Calculate the vapor pressure of water
above the solution. The vapor pressure of pure water at this
temperature is 0.0313 atm. Assume complete dissociation.
Which of the following types of substances are weak electrolytes
in aqueous solution at 298 K? CHOOSE ALL CORRECT ANSWERS, there may
be more than one correct answer.
weak acids
strong bases
aminium salts
ionic salts
metals
strong acids
weak bases
non-metals
metalloids