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

Potassium is a soft element belonging to Group 1 having symbol K. Let us discuss how K reacts with H₂SO₄ in this article.

Sulphuric acid (H₂SO₄) and potassium (K) react with each other to form salt and gas. Sulphuric acid is a viscous acid with no odour and colour. Potassium is an alkali metal with atomic number 19. It reacts vigorously with water and oxygen.

We will discuss some useful facts about H₂SO₄ + K, like reaction type, products, reaction enthalpy and balanced chemical equation through this article.

What is the product of H₂SO₄ and K

Potassium sulphate (K₂SO₄) and Hydrogen gas are the products formed when H₂SO₄ reacts with K. The chemical equation for this reaction is,

H₂SO₄ + K = K₂SO₄ + H₂

What type of reaction is H₂SO₄ + K

H₂SO₄ + K is an acid-metal reaction. Here H₂SO₄ is a strong acid and K is a metal.

How to balance H₂SO₄ + K

The balanced chemical equation for the H₂SO₄ + K reaction is,

H₂SO₄ + 2K = K₂SO₄ + H₂

The steps mentioned below must be used to derive the balanced chemical equation:

• The general unbalanced equation for H₂SO₄ + K reaction is,
  H₂SO₄ + K = K₂SO₄ + H₂

• Check if the number of moles of every single atom on both sides of the equation is equal or not.

• The number of potassium atom is not equal and can be equated by multiplying a coefficient of 2 with K on the left side of the equation.

• Thus, the balanced chemical equation is,
  H₂SO₄ + 2K = K₂SO₄ + H₂

H₂SO₄ + K titration

Titration of H₂SO₄ + K is not feasible because potassium (K) is a metal and cannot be categorised in any titration.

H₂SO₄ + K net ionic equation

H₂SO₄ + K net ionic equation is,

2H⁺ (aq.) + SO₄^2- (aq.) + 2K (s) = 2K⁺ (aq.) + SO₄^2- (aq.) + H₂ (g)

Following steps are involved in deriving the net ionic equation:

• Write the balanced molecular equation for the above reaction.
  H₂SO₄ + 2K = K₂SO₄ + H₂

• Denote the chemical states (s, l, g, aq) of each compound involved during the reaction.
  H₂SO₄ (aq.) + 2K (s) = K₂SO₄ (aq.) + H₂ (g)

• Split the strong electrolytes into corresponding ions to obtain the total ionic equation.
  2H⁺ (aq.) + SO₄^2- (aq.) + 2K (s) = 2K⁺ (aq.) + SO₄^2- (aq.) + H₂ (g)

• Cancel the spectator ions present in the equation to obtain the net ionic equation. Thus, the net ionic equation is,
  2H⁺ (aq.) + 2K (s) = 2K⁺ (aq.) + H₂ (g)

H₂SO₄ + K conjugate pairs

H₂SO₄ + K collectively do not have any conjugate pair. Conjugate pair of H₂SO₄ contains H₂SO₄ and its conjugate base is HSO₄^–.

H₂SO₄ and K intermolecular forces

• The intermolecular forces between H₂SO₄ molecules are London dispersion forces, dipole-dipole interaction and hydrogen bonding.

• H₂ contains weak London dispersion forces.

H₂SO₄ + K reaction enthalpy

H₂SO₄ + K reaction enthalpy is -504.8 kJ/mol. The standard enthalpy of formation for different compounds involved in the reaction is,

Molecules	Enthalpy of formation (in kJ/mol)
H2SO4	-909.27
K	0
K2SO4	-1165.11
H2	0

Enthalpy of reaction (ΔH_f) = Standard enthalpy of formation of products – standard enthalpy of formation of reactants

Thus, ΔH_{f =} (-1165.11 – 0) – (-909.27 – 0)

ΔH_f = -504.8 kJ/mol

Is H₂SO₄ + K a buffer solution

H₂SO₄ + K does not form a buffer solution because H₂SO₄ is a strong acid, but for a buffer solution there must exist a weak acid.

Is H₂SO₄ + K a complete reaction

H₂SO₄ + K is a complete reaction and no further process is left in this reaction.

Is H₂SO₄ + K an exothermic or endothermic reaction

H₂SO₄ + K is an exothermic reaction because reaction enthalpy has a negative value.

Is H₂SO₄ + K a redox reaction

H₂SO₄ + K is a redox reaction in which the hydrogen atom is getting reduced and the potassium atom is getting oxidised.

Is H₂SO₄ + K a precipitation reaction

H₂SO₄ + K is not a precipitation reaction because no solid products are formed after the process.

Is H₂SO₄ + K reversible or irreversible reaction

H₂SO₄ + K is an irreversible reaction because the H₂ gas once evolved, cannot be reverted back into the reaction mixture.

Is H₂SO₄ + K displacement reaction

H₂SO₄ + K is a single displacement reaction in which K displaces H₂ from H₂SO₄ to form K₂SO₄.

Conclusion

This article concludes that hydrochloric acid and potassium are highly reactive and must be handled carefully. K is kept submerged in seawater to prevent it from reacting with air or moisture.