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) + SO42-(Aq) = MgF2(s) + 2H+(Aq) + SO42-(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.

exo 2 2
Exothermic graph

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.