15 Facts on HF + MgSO4: What, How to Balance & FAQs

HF is weak acid reacts with inorganic salt MgSO₄ to give salt and acid respectively. Let us see, how they react

HF is colorless weak hydrohalic acid with PKa value of 4. It is used as important feedstock in preparation of important compound and pharmaceutical polymer as well. MgSO₄ is white crystalline solid inorganic salt mainly used as agricultural plant nutrients.

In this article, we will study, how reaction takes place between molecules, their conjugate pairs and its reaction in balanced form.

What is product of HF and MgSO₄

HF reacts with MgSO₄ to give corresponding salt MgF₂ and H₂SO₄.

HF + MgSO₄ = MgF₂ + H₂SO₄

What type of reaction is HF + MgSO₄

HF + MgSO₄ show double displacement reaction also called as salt metathesis reaction.

How to balance HF + MgSO₄

For the given reaction

HF + MgSO₄ = MgF2 + H2SO4

• Each reactant and product side should be represented with alphanumeric terminologies.
• A HF + B MgSO₄ = C MgF₂ + D H₂SO₄
• To indicate the chemicals in a given reaction, expressed coefficients are used to represent, each atom within the molecule.
• H= A+2D, F= A+2C, Mg= B+C, S=B+D, O= 4B+4D
• For estimating and validating the outcome, substitute the coefficient values into the gaussian elimination techniques.
• A = 2 , B=1 , C=1 , D=1
• Putting the coefficient value in respective place, we will get the balanced form of reaction, as:
• 2 HF + MgSO₄ = MgF₂ + H₂SO₄

HF + MgSO₄ titration

HF + MgSO₄ do not show titration. Hydro fluoric acid tend to give acid base titration with salt MgSO₄ but due to its neutrality and constituting both strong H₂SO₄ and strong MgOH base, it contradicts to give redox titration.

HF + MgSO₄ net ionic equation

Net ionic equation, for given reaction is

2F^–( Aq ) + Mg²⁺( Aq ) = MgF₂(s)

• Every compound’s phase should be taken into account while balancing a molecular equation.
• 2 HF(Aq) + MgSO₄ ( Aq ) = MgF₂ ( S ) + H₂SO₄ ( Aq )
• The aqueous salts or chemicals in the equation need to be made into ions. Only the strong electrolytes should be broken down since they completely dissociate.
• Here, HF, MgSO₄ and H₂SO₄ gets dissociated.
• 2H⁺(Aq) + 2F^–(Aq) + Mg²⁺(Aq) + SO₄^2-(Aq) = MgF₂(s) + 2H⁺(Aq) + SO4^2-(Aq)
• The spectator ions must be cancelled out in order to show species, actually involved in reaction.
• The remaining substance is net ionic equation.
• 2F^–(Aq) + Mg²⁺(Aq) = MgF₂(s)

HF + MgSO₄ conjugate pairs

HF + MgSO₄ conjugate pairs are as follows

• HF is weak acid undergoes deprotonation to give F_^– .
• No conjugate pair is available for salt MgSO₄.
• H₂SO₄ deprotonates to give HSO₄^–.
• MgF₂ do not constitute conjugate pairs.

HF and MgSO₄ intermolecular forces

HF and MgSO₄ intermolecular forces are

• HF show hydrogen bonding, London dispersion forces and dipole-dipole interaction due to presence of electro negativity differences between H and F molecule.
• MgSO₄ shows dipole dipole forces, London dispersion forces along with ionic bonds present in it.
• H₂SO₄ shows London dispersion forces, due to the existence of transient positive and negative charge regions.
• MgF₂ show strong ionic attraction present in it because of electronegative difference between Mg and F atom.

HF + MgSO₄ reaction enthalpy

HF + MgSO₄ reaction enthalpy is -800.9.

• The enthalpy of formation of HF is 57.3 KJ/Mol.
• The enthalpy of formation of MgSO₄ is 18.3 KJ/Mol.
• The enthalpy of formation of H₂SO₄ is -814.4 KJ/Mol.
• The enthalpy of formation of MgF₂ is 146.4 KJ/Mol.
• Enthalpy of reaction = [ 2(57.3) + (18.3)] – [ (-814.4) + (146.4)]

Is HF + MgSO₄ a buffer solution

In the reaction HF + MgSO₄, the mixture of HF and MgSO₄ forms a buffer solution. A buffer solution is formed between a weak acid and its conjugate base or vice versa, here HF is weak acid and MgSO₄ is conjugate base.

Is HF + MgSO₄ a complete reaction

HF + MgSO₄ is not a complete reaction because of weak acidic nature of hydrofluoric acid to resist 100% dissociation, hence some reactant molecule will remain in solution.

Is HF + MgSO₄ an exothermic or endothermic reaction

HF + MgSO₄ is exothermic in nature. Reaction will proceed with evolution of heat.

Is HF + MgSO₄ a redox reaction

HF + MgSO₄ is not redox reaction. Here, oxidation state of both reactant and product molecule is same.

Is HF + MgSO₄ a precipitation reaction

HF + MgSO₄ is precipitation reaction because of formation of white crystalline precipitate of MgF₂ salt, which is insoluble in water but soluble in strong acid during the course of reaction.

Is HF + MgSO₄ reversible or irreversible in nature

HF + MgSO₄ is irreversible in nature because of formation of precipitate. However, HF is weak acid so MgF₂ do not get dissolved in it.

Is HF + MgSO₄ displacement reaction

HF + MgSO₄ is double displacement reaction, swapping of bonds takes place within two reactant molecules to give two distinct products on preceeding of reaction.

Conclusion

HF + MgSO₄ is exothermic irreversible reaction because of negative reaction enthalpy and due to formation of precipitate MgF₂. Magnesium fluoride is transparent naturally occurring mineral, commercially used product in optics and for space telescope.

Sana Khan

Hello ….I am Sana Khan. A master’s student in organic chemistry from Nagpur University. I want to share my knowledge by publishing articles.