15 Facts on H2SO4 + NH3: What, How To Balance & FAQs

H₂SO₄ or sulphuric acid appears as a colorless oily liquid and NH₃ or ammonia is a Lewis base. Let us dive into the essential aspects of the reaction between H₂SO₄ and NH_3.

Sulphuric acid, an oxoacid of sulfur, is hygroscopic in nature. The aqueous solution of ammonia, a pungent and volatile gas, is known as ammonium hydroxide (NH₄OH). NH₃ is the hydride of the nitrogen atom.

As we move down, we will be able to grasp all the vital characteristics of the reaction.

What is the product of H₂SO₄ and NH₃

For the reaction H₂SO₄ + NH₃, ammonium sulfate [(NH₄)₂SO₄] is the only product.

H₂SO₄ + NH₃  =  (NH₄)₂SO₄

What type of reaction is H₂SO₄ and NH₃

H₂SO₄ + NH₃ belongs to the combination reaction category as H₂SO₄ and NH₃ combine to produce (NH₄)₂SO₄ as the single product.

How to balance H₂SO₄ and NH₃

For the reaction H₂SO₄ + NH₃, the balanced equation is

H₂SO₄ + 2NH₃ = (NH₄)₂SO₄  

Following steps are required to acquire the balanced equation.

• Write the chemical equation for the reaction.
• H₂SO₄ + NH₃ = (NH₄)₂SO₄ 
• In this equation, the number of S and O atoms is 1 and 4, respectively, on both sides.
• H₂SO₄ + NH₃ = (NH₄)₂SO₄ 
• The number of H atoms is 5 on the left-hand side and 8 on the right-hand side of the equation.
• H₂SO₄ + NH₃ = (NH₄)₂SO₄ 
• The number of N atoms is 1 on the left-hand side and 2 on the right-hand side of the equation.
• H₂SO₄ + NH₃ = (NH₄)₂SO₄ 
• Multiply NH₃ by 2 so that number of H and N becomes the same on both sides.
• Finally, the balanced equation is
• H₂SO₄ + 2NH₃ = (NH₄)₂SO₄ 

H₂SO₄ and NH₃ titration

To determine the concentration of NH₃ by H₂SO₄ or vice versa, we have to follow the steps mentioned below.

Apparatus

Volumetric flask, titration stand, pipette, burette, measuring cylinder, and conical flask.

Indicator

For titration of NH₃ by H₂SO₄, an ideal indicator is phenolphthalein.

Procedure

• Take NH₄OH, which is an aqueous solution of the gas NH₃, in a conical flask.
• Add 2-3 drops of indicator and mix it well.
• Titrate NH₄OH with H₂SO₄ taken in burette until the solution persists to a faint pink color.
• Repeat the titration a few times to keep away from manual errors and calculate the average burette reading.
• Finally, the concentration of NH₃ which is same as that of NH₄OH or the concentration of H₂SO₄ is determined using the formula S₁V₁ = S₂V₂.

H₂SO₄ and NH₃ net ionic equation

For H₂SO₄ + NH₃, the net ionic equation is

H⁺ (aq) + NH₃ (g) = NH₄⁺ (aq)

Follow the steps underneath to derive the net ionic equation.

• Both the reactants, being soluble and ionic in nature, can ionize into respective ions.
• The complete ionic equation is
• 2H⁺ (aq) + SO₄^2- (aq) + 2NH₃ (g)  =  2NH₄⁺ (aq) + SO₄^2-
• Sulfate (SO₄^2-) ion is the only spectator ion here.
• After canceling the SO₄^2- ion from both sides, we get
• 2H⁺ (aq) + 2NH₃ (g) = 2NH₄⁺ (aq)
• Finally, we get the net ionic equation by reducing the above equation.
• H⁺ (aq) + NH₃ (g) = NH₄⁺ (aq)

H₂SO₄ and NH₃ conjugate pairs

In the reaction H₂SO₄ + NH₃, the conjugate pairs are

• Hydrogen sulfate ion (HSO₄^–) is the conjugate pair of the acid H₂SO₄.
• Ammonium ion (NH₄⁺) is the conjugate pair of the base NH₃.

H₂SO₄ and NH₃ intermolecular forces

In the reaction H₂SO₄ + NH₃, intermolecular forces are

• Dipole-dipole and hydrogen bonding interactions are present in H₂SO₄ molecule, of which the second one is dominant.
• Hydrogen bond is present in NH₃ molecule.

H₂SO₄ and NH₃ reaction enthalpy

For H₂SO₄ + NH₃, the reaction enthalpy value is -179.3 kJ/mole. It is calculated as follows.

Compounds	Enthalpy of formation (ΔHf°) in kJ/mole
H2SO4 (aq)	-909.3
NH3 (g)	-46.1
(NH4)2SO4(s)	-1180.8

• Reaction Enthalpy = ΣΔH_f°(products) – ΣΔH_f° (reactants)  
• =  (-1180.8) – [(-909.3) + 2*(-46.1)] KJ/mol
• = -179.3 KJ/mol

Is H₂SO₄ and NH₃ a buffer solution

H₂SO₄ + NH₃ cannot be a buffer solution as in a buffer solution; a weak base like NH₃ must be present along with its conjugate acid NH₄⁺ ion but after a complete reaction, there is only NH₄⁺ ion in the product molecule and no NH₃.

Is H₂SO₄ and NH₃ a complete reaction

H₂SO₄ + NH₃ is a complete reaction because, after forming ammonium sulfate, further reaction is not observed.

Is H₂SO₄ and NH₃ an exothermic or endothermic reaction

H₂SO₄ + NH₃ is exothermic in nature as heat is given out during the reaction.

Is H₂SO₄ and NH₃ a redox reaction

H₂SO₄ + NH₃ is not a redox reaction, as after the reaction, the oxidation states for all the atoms remain the same.

H₂⁺¹S⁺⁶O₄^-2 +  N^-3H₃⁺¹   =    (N^-3H₄⁺¹)₂S⁺⁶O₄^-2

Is H₂SO₄ and NH₃ a precipitation reaction

H₂SO₄ + NH₃ is not a precipitation reaction as the product ammonium sulfate is a highly water-soluble compound.

Is H₂SO₄ and NH₃ reversible or irreversible reaction

H₂SO₄ + NH₃ is an irreversible reaction as it occurs only towards right-hand side.

Is H₂SO₄ and NH₃ displacement reaction

H₂SO₄ + NH₃ is not a displacement reaction as the sulfate ion present in sulfuric acid is not exchanged with another reactant NH₃.

Conclusion

In conclusion, the product (NH₄)₂SO₄ is a highly water-soluble, white, and crystalline solid. In an aqueous medium, it can dissociate into NH₄⁺ cation and SO₄^2- anion. The most important application of this compound is as nitrogen containing fertilizer.