You-iggy

KSCN + 5HNO3 → KHSO4 + NH4NO3 + 2N2O3↑ + CO2

The reaction of potassium thiocyanate and nitric acid yields potassium hydrogensulfate, ammonium nitrate, dinitrogen trioxide, and carbon dioxide (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:

Table of contents
  1. 1Reaction data
  2. 2Thermodynamic changes
  3. 3References
  4. 4Related reactions
  5. 5Related categories

Reaction data

Chemical equation

General equation

Reaction of reducing species and oxidizing species
Reducing speciesReducing agent + Oxidizing speciesOxidizing agent
ProductOxidation product + ProductReduction product

Oxidation state of each atom

Reactants

Chemical formulaNameCoefficientTypeType in general
equation
KSCNPotassium thiocyanate1
Reducing
Reducing
HNO3Nitric acid5
Oxidizing
Oxidizing

Products

Chemical formulaNameCoefficientTypeType in general
equation
KHSO4Potassium hydrogensulfate1
Oxidized
NH4NO3Ammonium nitrate1
N2O3Dinitrogen trioxide2
Reduced
CO2Carbon dioxide1

Thermodynamic changes

Changes in standard condition

Reaction of potassium thiocyanate and nitric acid
ΔrG−748.7 kJ/mol
K1.47 × 10131
pK−131.17
KSCNCrystalline solid + 5HNO3Liquid
KHSO4Crystalline solid + NH4NO3Crystalline solid + 2N2O3Gas + CO2Gas
Standard enthalpy
of reaction
ΔrH°
kJ · mol−1
Standard
Gibbs energy
of reaction
ΔrG°
kJ · mol−1
Standard entropy
of reaction
ΔrS°
J · K−1 · mol−1
Standard heat
capacity of reaction
at constant pressure
ΔrCp°
J · K−1 · mol−1
per 1 mol of
Equation
−681.6−748.7225.2
−681.6−748.7225.2
per 1 mol of
−136.3−149.745.04
−681.6−748.7225.2
per 1 mol of
−681.6−748.7225.2
−340.8−374.4112.6
per 1 mol of
−681.6−748.7225.2

Changes in aqueous solution (1)

Reaction of potassium thiocyanate and nitric acid
ΔrG−598.37 kJ/mol
K6.76 × 10104
pK−104.83
KSCNIonized aqueous solution + 5HNO3Ionized aqueous solution
KHSO4Ionized aqueous solution + NH4NO3Ionized aqueous solution + 2N2O3Gas + CO2Gas
Standard enthalpy
of reaction
ΔrH°
kJ · mol−1
Standard
Gibbs energy
of reaction
ΔrG°
kJ · mol−1
Standard entropy
of reaction
ΔrS°
J · K−1 · mol−1
Standard heat
capacity of reaction
at constant pressure
ΔrCp°
J · K−1 · mol−1
per 1 mol of
Equation
−492.92−598.37353.5550
−492.92−598.37353.5550
per 1 mol of
−98.584−119.6770.70110
−492.92−598.37353.5550
per 1 mol of
−492.92−598.37353.5550
−246.46−299.19176.8275
per 1 mol of
−492.92−598.37353.5550

Changes in aqueous solution (2)

Reaction of potassium thiocyanate and nitric acid
ΔrG−589.99 kJ/mol
K2.30 × 10103
pK−103.36
KSCNIonized aqueous solution + 5HNO3Ionized aqueous solution
KHSO4Ionized aqueous solution + NH4NO3Ionized aqueous solution + 2N2O3Gas + CO2Un-ionized aqueous solution
Standard enthalpy
of reaction
ΔrH°
kJ · mol−1
Standard
Gibbs energy
of reaction
ΔrG°
kJ · mol−1
Standard entropy
of reaction
ΔrS°
J · K−1 · mol−1
Standard heat
capacity of reaction
at constant pressure
ΔrCp°
J · K−1 · mol−1
per 1 mol of
Equation
−513.21−589.99257.4
−513.21−589.99257.4
per 1 mol of
−102.64−118.0051.48
−513.21−589.99257.4
per 1 mol of
−513.21−589.99257.4
−256.61−295.00128.7
per 1 mol of
−513.21−589.99257.4

Thermodynamic data of reactants

Chemical formulaStandard enthalpy
of formation
ΔfH°
kJ · mol−1
Standard Gibbs
energy of
formation
ΔfG°
kJ · mol−1
Standard
molar entropy
S°
J · K−1 · mol−1
Standard molar
heat capacity at
constant pressure
Cp°
J · K−1 · mol−1
KSCN (cr)-200.16[1]-178.31[1]124.26[1]88.53[1]
KSCN (ai)-175.94[1]-190.56[1]246.9[1]-18.4[1]
HNO3 (l)-174.10[1]-80.71[1]155.60[1]109.87[1]
HNO3 (g)-135.06[1]-74.72[1]266.38[1]53.35[1]
HNO3 (ai)-207.36[1]-111.25[1]146.4[1]-86.6[1]
HNO3 (l)
1 hydrate
-473.46[1]-328.77[1]216.90[1]182.46[1]
HNO3 (l)
3 hydrate
-1056.04[1]-811.09[1]346.98[1]325.14[1]
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (g):Gas

Thermodynamic data of products

Chemical formulaStandard enthalpy
of formation
ΔfH°
kJ · mol−1
Standard Gibbs
energy of
formation
ΔfG°
kJ · mol−1
Standard
molar entropy
S°
J · K−1 · mol−1
Standard molar
heat capacity at
constant pressure
Cp°
J · K−1 · mol−1
KHSO4 (cr)-1160.6[1]-1031.3[1]138.1[1]
KHSO4 (ai)-1139.72[1]-1039.18[1]234.3[1]-63[1]
NH4NO3 (cr)-365.56[1]-183.87[1]151.08[1]139.3[1]
NH4NO3 (ai)-339.87[1]-190.56[1]259.8[1]-6.7[1]
N2O3 (l)50.29[1]
N2O3 (g)83.72[1]139.46[1]312.28[1]65.61[1]
CO2 (g)-393.509[1]-394.359[1]213.74[1]37.11[1]
CO2 (ao)-413.80[1]-385.98[1]117.6[1]
* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (g):Gas, (ao):Un-ionized aqueous solution

References

List of references

  1. 1
    Janiel J. Reed (1989)
    The NBS Tables of Chemical Thermodynamic Properties: Selected Values for Inorganic and C1 and C2 Organic Substances in SI Units
    National Institute of Standards and Technology (NIST)