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9H2 + 2AgSCN → 2Ag + (NH4)2S + H2S + 2CH4

9H₂ + 2AgSCN → 2Ag + (NH₄)₂S + H₂S + 2CH₄

Last updated: June 13, 2022

Reaction of hydrogen and silver(I) thiocyanate: 9H₂Hydrogen + 2AgSCNSilver(I) thiocyanate
⟶
2AgSilver + (NH₄)₂SAmmonium sulfide + H₂SHydrogen sulfide + 2CH₄Methane

The reaction of hydrogen and silver(I) thiocyanate yields silver, ammonium sulfide, hydrogen sulfide, and methane (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:

Reaction of reducing species and reducible species

Table of contents

Reaction data

Chemical equation

Reaction of hydrogen and silver(I) thiocyanate: 9H₂Hydrogen + 2AgSCNSilver(I) thiocyanate
⟶
2AgSilver + (NH₄)₂SAmmonium sulfide + H₂SHydrogen sulfide + 2CH₄Methane

General equation

Reaction of reducing species and reducible species: Reducing speciesReducing agent + Reducible speciesOxidizing agent
⟶
ProductOxidation product + ProductReduction product

Oxidation state of each atom

Reaction of hydrogen and silver(I) thiocyanate

Reactants

Chemical formula	Name	Coefficient	Type	Type in general equation
H₂	Hydrogen	9	Reducing	Reducing
AgSCN	Silver(I) thiocyanate	2	Oxidizing	Reducible

Products

Chemical formula	Name	Coefficient	Type	Type in general equation
Ag	Silver	2	Reduced	–
(NH₄)₂S	Ammonium sulfide	1	Oxidized	–
H₂S	Hydrogen sulfide	1	Oxidized	–
CH₄	Methane	2	Redoxed product	–

Thermodynamic changes

Changes in aqueous solution (1)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −705.6 kJ/mol K 4.13 × 10¹²³ pK −123.62: 9H₂Un-ionized aqueous solution + 2AgSCNIonized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SGas + 2CH₄Gas

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	−728.3	−705.6	−4752	–
per 1 mol of Hydrogen	−80.92	−78.40	−528.0	–
per 1 mol of Silver(I) thiocyanate	−364.1	−352.8	−2376	–
per 1 mol of Silver	−364.1	−352.8	−2376	–
per 1 mol of Ammonium sulfide	−728.3	−705.6	−4752	–
per 1 mol of Hydrogen sulfide	−728.3	−705.6	−4752	–
per 1 mol of Methane	−364.1	−352.8	−2376	–

Changes in aqueous solution (2)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −672.8 kJ/mol K 7.40 × 10¹¹⁷ pK −117.87: 9H₂Un-ionized aqueous solution + 2AgSCNIonized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SGas + 2CH₄Un-ionized aqueous solution

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	−756.7	−672.8	−4957	–
per 1 mol of Hydrogen	−84.08	−74.76	−550.8	–
per 1 mol of Silver(I) thiocyanate	−378.4	−336.4	−2479	–
per 1 mol of Silver	−378.4	−336.4	−2479	–
per 1 mol of Ammonium sulfide	−756.7	−672.8	−4957	–
per 1 mol of Hydrogen sulfide	−756.7	−672.8	−4957	–
per 1 mol of Methane	−378.4	−336.4	−2479	–

Changes in aqueous solution (3)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −699.9 kJ/mol K 4.14 × 10¹²² pK −122.62: 9H₂Un-ionized aqueous solution + 2AgSCNIonized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SUn-ionized aqueous solution + 2CH₄Gas

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	−747.3	−699.9	−4836	–
per 1 mol of Hydrogen	−83.03	−77.77	−537.3	–
per 1 mol of Silver(I) thiocyanate	−373.6	−349.9	−2418	–
per 1 mol of Silver	−373.6	−349.9	−2418	–
per 1 mol of Ammonium sulfide	−747.3	−699.9	−4836	–
per 1 mol of Hydrogen sulfide	−747.3	−699.9	−4836	–
per 1 mol of Methane	−373.6	−349.9	−2418	–

Changes in aqueous solution (4)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −667.1 kJ/mol K 7.43 × 10¹¹⁶ pK −116.87: 9H₂Un-ionized aqueous solution + 2AgSCNIonized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SUn-ionized aqueous solution + 2CH₄Un-ionized aqueous solution

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	−775.8	−667.1	−5042	–
per 1 mol of Hydrogen	−86.20	−74.12	−560.2	–
per 1 mol of Silver(I) thiocyanate	−387.9	−333.6	−2521	–
per 1 mol of Silver	−387.9	−333.6	−2521	–
per 1 mol of Ammonium sulfide	−775.8	−667.1	−5042	–
per 1 mol of Hydrogen sulfide	−775.8	−667.1	−5042	–
per 1 mol of Methane	−387.9	−333.6	−2521	–

Changes in aqueous solution (5)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −651.4 kJ/mol K 1.32 × 10¹¹⁴ pK −114.12: 9H₂Un-ionized aqueous solution + 2AgSCNUn-ionized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SGas + 2CH₄Gas

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	–	−651.4	–	–
per 1 mol of Hydrogen	–	−72.38	–	–
per 1 mol of Silver(I) thiocyanate	–	−325.7	–	–
per 1 mol of Silver	–	−325.7	–	–
per 1 mol of Ammonium sulfide	–	−651.4	–	–
per 1 mol of Hydrogen sulfide	–	−651.4	–	–
per 1 mol of Methane	–	−325.7	–	–

Changes in aqueous solution (6)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −618.6 kJ/mol K 2.37 × 10¹⁰⁸ pK −108.37: 9H₂Un-ionized aqueous solution + 2AgSCNUn-ionized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SGas + 2CH₄Un-ionized aqueous solution

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	–	−618.6	–	–
per 1 mol of Hydrogen	–	−68.73	–	–
per 1 mol of Silver(I) thiocyanate	–	−309.3	–	–
per 1 mol of Silver	–	−309.3	–	–
per 1 mol of Ammonium sulfide	–	−618.6	–	–
per 1 mol of Hydrogen sulfide	–	−618.6	–	–
per 1 mol of Methane	–	−309.3	–	–

Changes in aqueous solution (7)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −645.7 kJ/mol K 1.32 × 10¹¹³ pK −113.12: 9H₂Un-ionized aqueous solution + 2AgSCNUn-ionized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SUn-ionized aqueous solution + 2CH₄Gas

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	–	−645.7	–	–
per 1 mol of Hydrogen	–	−71.74	–	–
per 1 mol of Silver(I) thiocyanate	–	−322.9	–	–
per 1 mol of Silver	–	−322.9	–	–
per 1 mol of Ammonium sulfide	–	−645.7	–	–
per 1 mol of Hydrogen sulfide	–	−645.7	–	–
per 1 mol of Methane	–	−322.9	–	–

Changes in aqueous solution (8)

Reaction of hydrogen and silver(I) thiocyanate ◆ Δ_rG −612.9 kJ/mol K 2.37 × 10¹⁰⁷ pK −107.38: 9H₂Un-ionized aqueous solution + 2AgSCNUn-ionized aqueous solution
⟶
2AgCrystalline solid + (NH₄)₂SIonized aqueous solution + H₂SUn-ionized aqueous solution + 2CH₄Un-ionized aqueous solution

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	–	−612.9	–	–
per 1 mol of Hydrogen	–	−68.10	–	–
per 1 mol of Silver(I) thiocyanate	–	−306.4	–	–
per 1 mol of Silver	–	−306.4	–	–
per 1 mol of Ammonium sulfide	–	−612.9	–	–
per 1 mol of Hydrogen sulfide	–	−612.9	–	–
per 1 mol of Methane	–	−306.4	–	–

Thermodynamic data of reactants

Chemical formula	Standard enthalpy of formation Δ_fH° kJ · mol⁻¹	Standard Gibbs energy of formation Δ_fG° kJ · mol⁻¹	Standard molar entropy S° J · K⁻¹ · mol⁻¹	Standard molar heat capacity at constant pressure C_p° J · K⁻¹ · mol⁻¹
H₂ (g)	0^[1]	0^[1]	130.684^[1]	28.824^[1]
H₂ (ao)	-4.2^[1]	17.6^[1]	577^[1]	–
AgSCN (cr)	87.9^[1]	101.39^[1]	131.0^[1]	63^[1]
AgSCN (ai)	182.00^[1]	169.80^[1]	217.1^[1]	-18.4^[1]
AgSCN (ao)	–	142.7^[1]	–	–

* (g):Gas, (ao):Un-ionized aqueous solution, (cr):Crystalline solid, (ai):Ionized aqueous solution

Thermodynamic data of products

Chemical formula	Standard enthalpy of formation Δ_fH° kJ · mol⁻¹	Standard Gibbs energy of formation Δ_fG° kJ · mol⁻¹	Standard molar entropy S° J · K⁻¹ · mol⁻¹	Standard molar heat capacity at constant pressure C_p° J · K⁻¹ · mol⁻¹
Ag (cr)	0^[1]	0^[1]	42.55^[1]	25.351^[1]
Ag (g)	284.55^[1]	245.65^[1]	172.997^[1]	20.786^[1]
(NH₄)₂S (ai)	-231.8^[1]	-72.6^[1]	212.1^[1]	–
H₂S (g)	-20.63^[1]	-33.56^[1]	205.79^[1]	34.23^[1]
H₂S (ao)	-39.7^[1]	-27.83^[1]	121^[1]	–
CH₄ (g)	-74.81^[1]	-50.72^[1]	186.264^[1]	35.309^[1]
CH₄ (ao)	-89.04^[1]	-34.33^[1]	83.7^[1]	–

* (cr):Crystalline solid, (g):Gas, (ai):Ionized aqueous solution, (ao):Un-ionized aqueous solution

References

List of references

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
https://doi.org/10.18434/M32124
National Institute of Standards and Technology (NIST)
Citation list

Δ_rG	−705.6 kJ/mol
K	4.13 × 10¹²³
pK	−123.62

Δ_rG	−672.8 kJ/mol
K	7.40 × 10¹¹⁷
pK	−117.87

Δ_rG	−699.9 kJ/mol
K	4.14 × 10¹²²
pK	−122.62

Δ_rG	−667.1 kJ/mol
K	7.43 × 10¹¹⁶
pK	−116.87

9H2 + 2AgSCN → 2Ag + (NH4)2S + H2S + 2CH4

Reaction data

Chemical equation

General equation

Oxidation state of each atom

Reactants

Products

Thermodynamic changes

Changes in aqueous solution (1)

Changes in aqueous solution (2)

Changes in aqueous solution (3)

Changes in aqueous solution (4)

Changes in aqueous solution (5)

Changes in aqueous solution (6)

Changes in aqueous solution (7)

Changes in aqueous solution (8)

Thermodynamic data of reactants

Thermodynamic data of products

References

List of references

Related reactions

Reactions with same reactants

Related categories

Type of reaction

General equation

Reactant

Product

9H₂ + 2AgSCN → 2Ag + (NH₄)₂S + H₂S + 2CH₄