13 Facts on HCl + Ag2S: What, How To Balance & FAQs

An aqueous solution of hydrogen chloride is hydrochloric acid, also known as muriatic acid. Let us see the different aspects of the HCl-Ag2S reaction.

HCl is a corrosive colorless acid made by dissolving gaseous hydrogen chloride in water. Silver sulfide, also known as Ag2S, is an inorganic compound. It is the only silver sulfide and is a thick black solid. It can be used as a photosensitizer in photography.

As the article progresses, all of the critical aspects of the HCl-Ag2S reaction will become clear.

What is the product of HCl and Ag2S?

When HCl and Ag2S react, silver chloride (AgCl) and hydrogen sulfide (H2S) gas are formed.

The reaction equation is as follows:

Ag2S + 2HCl → 2AgCl + H2S

What type of reaction is HCl + Ag2S?

The reaction HCl + Ag2S is a double displacement reaction.

How to balance HCl + Ag2S?

In the HCl+Ag2S reaction, the steps to equate the above reaction scheme are as follows:

  • Ag2S + HCl → AgCl + H2S
  • Step 1: Multiply AgCl by 2 to equal Ag2S, keeping in mind that both sides should be equal in atoms.
  • Ag2S + HCl → 2AgCl + H2S
  • Step 2: Because the product side contains two hydrogen atoms, multiply HCl by two.
  • Ag2S + 2HCl → 2AgCl + H2S
  • The reactant and product sides are now equal. On both sides, there are 2 hydrogens, 2 silvers, 2 chlorines, and 1 sulfur atom.
  • The equation is now balanced.

HCl + Ag2S net ionic equation

To determine the net ionic equation for the HCl+Ag2reaction, follow these steps:

  • Determine each substance’s phase (for gas=g, for liquid=l, for solid/non-soluble=s, for aqueous/soluble=aq).
  • Ag2S(s) + 2HCl(aq) → 2AgCl(s)+ H2S(s)
  • Make a list of all the soluble ionic compounds and their corresponding ions.
  • Ag2S(s) + 2H+(aq)+ 2Cl(aq) → 2AgCl(s) + H2S(s)
  • Ions that appear on both the reactant and product sides of the ionic equation must be removed.
  • Ag2S(s) + 2H+(aq)+ 2Cl(aq) → 2AgCl(s) + H2S(s)
  • This is the net ionic reaction equation.

HCl + Ag2S conjugate pairs

In the HCl+Ag2S reaction,

  • HCl is a powerful acid. When it donates a proton, it produces a Cl- ion, and thus Cl- is the conjugate base.
  • Strong acids degrade silver sulfide, which is insoluble in most solvents. It is not water-soluble.
Silver sulfide

HCl+ Ag2S reaction enthalpy

The HCl + Ag2S reaction enthalpy is 92.72 kJ/mol.

  • The enthalpy formation of AgCl is -127 kJ/mol.
  • The enthalpy formation of H2S is –20.17 kJ/mol.
  • The enthalpy formation of Ag2S is -32.59 kJ/mol.
  • The enthalpy formation of HCl is -167.15 kJ/mol.

Is HCl + Ag2S a buffer solution

HCl + Ag2S is not a buffer solution. Because,

  • Ag2S is an acid, it is much less soluble in water.
  • HCl is a powerful acid.
  • A buffer solution is formed when an aqueous solution containing a weak acid and its conjugate base, or vice versa, is combined.

Is HCl + Ag2S a complete reaction?

The reaction HCl + Ag2S is complete. As a result of the formation of a precipitate, AgCl crystallizes here.

Is HCl + Ag2S an exothermic or endothermic reaction?

The HCl + Ag2S reaction is endothermic and has a positive reaction enthalpy.

Is HCl + Ag2S a redox reaction?

The HCl + Ag2S reaction is not a redox reaction because no electrons are transferred during the reaction. Because there is no electron transfer, the oxidation state of all reacting species, including Ag, H, Cl, C, and O, remains constant from reactant to product.

Is HCl + Ag2S a precipitation reaction?

The HCl + Ag2S reaction is a precipitation reaction. Because the product is a white AgCl precipitate when HCl is added to a silver-ion solution, the positively charged silver ions combine with the negatively charged chloride ions.

Is HCl + Ag2S reversible or irreversible reaction?

The HCl + Ag2S reaction is irreversible. Because the precipitate formed in the product cannot be converted back to the solution, this is an example of an irreversible precipitation reaction.

Is HCl + Ag2S displacement reaction?

The HCl+Ag2O reaction is a double displacement reaction. The hydrogen ion in HCl is shifted by the silver metal ion during the formation of H2S gas, resulting in the formation of AgCl salt.

  • Ag2S + 2HCl → 2AgCl + H2S


The reaction between HCl and Ag2S produces AgCl as a precipitate. Silver sulfide is a network solid composed of silver (electronegativity of 1.98) and sulfur (electronegativity of 2.58), with low ionic character (about 10%). It undergoes double displacement reaction.