15 Facts on HCl + MgSO4: What, How To Balance & FAQs


HCl is an acid and MgSO4 is a salt. Let us have an idea of how they react to each other.

The chemical formula of hydrochloric acid is HCl and that of magnesium sulphate is MgSO4. HCl is an aqueous solution of hydrogen chloride gas that appears as colorless liquid. MgSO4 salt consists of Mg2+ cation and SO42- (sulphate) anion. It is a water soluble crystalline solid.

Here, we will talk about all the necessary aspects of the reaction between HCl and MgSO4 such as products, balancing the equation, nature of the reaction, etc.

What is the product of HCl and MgSO4

The products of the reaction HCl + MgSO4 are magnesium chloride (chemical formula MgCl2) and sulphuric acid (H2SO4). The reaction is shown below.

HCl (aq) + MgSO4 (aq)  =  MgCl2 (aq) + H2SO4 (aq)

What type of reaction is HCl + MgSO4

The type of the reaction HCl + MgSO4 is displacement reaction.

How to balance HCl + MgSO4

The unbalanced equation for the reaction HCl + MgSO4 is

HCl (aq) + MgSO4 (aq)  =  MgCl2 (aq) + H2SO4 (aq)

The following steps should be followed to get the balanced equation

  • Count the number of atoms of every element on the reactant side and product side.
  • The number of atoms of every element should be the same on the reactant side and product side.
  • If it is not the same, we have to multiply the formula by the smallest possible figure.
  • Here, the number of H and Cl atoms is not the same on both sides but the number of Mg, S, and O is the same on both sides.
  • To make the number of H and Cl atoms the same on both sides, we will multiply HCl with 2 on the left hand side.

The balanced equation is

2HCl (aq) + MgSO4 (aq)  =  MgCl2 (aq) + H2SO4 (aq)

HCl + MgSO4 titration

The titration between HCl and MgSO4 is impossible as it does not fall under any category of titration methods. There are mainly four types of titrations; acid-base, redox, precipitation, and complexometric.

HCl + MgSO4 net ionic equation

The complete reaction is as follows

2H+ (aq) + 2Cl (aq)  + Mg2+ (aq)  + SO42- (aq)   =   Mg2+ (aq)  + 2Cl (aq) + 2H+ (aq) + SO42- (aq)

As all the ions are spectator ions, there is no net reaction. We should write the complete ionic equation before writing the net ionic equation. It involves spectator ions which we can get by ionizing all the soluble ionic compounds into their respective cations and anions.

HCl + MgSO4 conjugate pairs

For the reaction HCl + MgSO4, the conjugate base of HCl is Cl. No conjugate pair is possible for MgSO4. Conjugate pairs (also called conjugate acid-base pairs) differ from each other by the presence or absence of a proton.

HCl + MgSO4 intermolecular forces

  • In HCl, two intermolecular forces are present; dipole-dipole and London dispersion forces of which the first one is predominant as HCl is polar molecule.
  • In MgSO4, three intermolecular forces are present; Ionic, dipole-dipole, and London dispersion of which the first one is predominant as MgSO4 is an ionic molecule.

HCl + MgSO4 reaction enthalpy

The value of reaction enthalpy for the reaction HCl + MgSO4 is around -87.3 kJ/mole. The reaction enthalpy is calculated by taking the difference between the enthalpies of formation of the products MgCl2 and H2SO4 and that of the reactants HCl and MgSO4.

Is HCl + MgSO4 a buffer solution

In the reaction HCl + MgSO4, the mixture of HCl and MgSO4 cannot form a buffer solution. A buffer solution is formed between a weak acid and its conjugate base or vice versa. Here, HCl is a strong acid and in MgSO4, the sulphate ion is not the conjugate base of HCl.

Is HCl + MgSO4 a complete reaction

The reaction HCl + MgSO4 is a complete reaction as after the formation of the products MgCl2 and H2SO4, further reaction is not possible.

Is HCl + MgSO4 an exothermic or endothermic reaction

The reaction HCl + MgSO4 is exothermic in nature as heat is released.

Is HCl + MgSO4 a redox reaction

The reaction HCl + MgSO4 is not a redox reaction as there is no change in the oxidation states of the atoms present in the reactant and product molecules.

Is HCl + MgSO4 a precipitation reaction

The reaction HCl + MgSO4 between HCl and MgSO4 is not a precipitation reaction. The product MgCl2 is soluble in water, and no precipitation occurs.

Is HCl + MgSO4 reversible or irreversible reaction

The reaction HCl + MgSO4 is an irreversible reaction.

Is HCl + MgSO4 displacement reaction

The reaction HCl + MgSO4 is a displacement reaction as two ions are exchanged between two molecules.

Conclusion

To conclude, we can say that when hydrochloric acid reacts with magnesium sulphate, the chloride ion of hydrochloric acid displaces the sulphate ion of magnesium sulphate forming magnesium chloride and sulphuric acid as products. Magnesium chloride is a salt and sulphuric acid is an acid.

Tuluma Das

Hello, I am Tuluma Das, Completed my Ph.D. in Organic Chemistry from the Indian Association for the Cultivation of Science. I have a total of 9 years of research experience including a Ph.D. and Postdoc and 3 years of teaching experience. I have published 7 papers so far in international journals. Let’s connect through Linkedin : https://www.linkedin.com/in/tuluma-das-90887a99/

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