15 Facts on H2SO4 +Mg2Si: What, How to Balance & FAQs

Magnesium silicide (Mg₂Si) is a crystalline solid inorganic compound. Let’s see its reaction with Sulfuric acid (H₂SO₄).

Mg₂Si is water-insoluble and denser than water. It forms a face-centered cubic antifluorite structure. Si^4- ion can be thought of as the main component of magnesium silicide. It reacts with acid. H₂SO₄ is highly soluble in water. It is available in oily, liquid form. It is one of the strongest acids available.

In this article, we shall discuss the reaction between H₂SO₄ + Mg₂Si, and some interesting facts.

1. What is the product of H₂SO₄ and Mg₂Si?

Silicon tetrahydride (SiH₄), also known as Silane, and Magnesium sulfate (MgSO₄) are formed as products by the reaction between H₂SO₄ and Mg₂Si. The reaction is,

H₂SO₄ + Mg₂Si → SiH₄ + MgSO₄

2. What type of reaction is H₂SO₄ + Mg₂Si?

The type of reaction between H₂SO₄ and Mg₂Si is a double displacement reaction, else known as Metathesis reaction.

3. How to balance H₂SO₄ + Mg₂Si?

To balance the equation between H₂SO₄ and Mg₂Si, we must determine whether an equal number of individual atoms (H, S, O, Mg, and Si) are present on both the reactant and product sides.

• Since four molecules are present, we first designate each one as A, B, C, and D.
• This is how the response appears: A H₂SO₄ + B Mg₂Si = C SiH₄ + D MgSO₄.
• Using the appropriate values, we now figure out how many coefficients are listed in the reactants and products as alphabets.

Element	Reaction side	Product side
Hydrogen	2A+ 0B	4C+0D
Sulfur	1A+ 0B	0C+1D
Oxygen	4A+0B	0C+4D
Magnesium	0A+2B	0C+1D
Silicon	0A+1B	1C+0D

• The Gaussian elimination procedure is used in Step 3 to get the coefficient and variables needed to balance the equation.
• A= 2(H₂SO₄), B= 1(Mg₂Si), C= 1(SiH₄), D= 2(MgSO₄)
• Now, an equal number of each element is present on both the reactant and product side.

Element	Reaction side	Product side
Hydrogen	4	4
Sulfur	2	2
Oxygen	8	8
Magnesium	2	2
Silicon	1	1

• The balanced equation of the reaction between H₂SO₄ and Mg₂Si is,
•  2H₂SO₄+ Mg₂Si = SiH₄ + 2MgSO₄.

4. H₂SO₄ + Mg₂Si titration

Titration between H₂SO₄ and Mg₂Si cannot be predicted as acid-base reaction though H₂SO₄ is a strong acid. Mg₂Si does not act as a base in the reaction. It does, however, indicate the possibility of redox titration with certain anomalies.

5. H₂SO₄+ Mg₂Si net ionic equation

H₂SO₄ and Mg₂Si reaction’s net ionic equation is,

4H⁺(aq) + Si^4-(s) = Si⁽⁴⁺⁾H₄^(-1) (g)

• A molecular equation needs to be balanced and consider each compound’s phase.
• 2H₂SO₄(aq) + Mg₂Si(s) → SiH₄(g) +2MgSO₄(s)
• It is necessary to convert the aqueous salts or chemicals in the equation into ions. Because they can entirely dissociate, only the strong electrolytes should be broken down.
• 4H⁺+2SO₄^2-+ 2Mg²⁺+Si^4- = Si⁴⁺+4H^– + 2Mg²⁺ + 2SO₄^2-
• We eliminate the spectator ions to reveal the species that are truly involved in the reaction.
• The net ionic equation is,
• 4H⁺(aq) + Si^4-(s) = Si⁽⁴⁺⁾H₄^(-1)(g)

6. H₂SO₄ + Mg₂Si conjugate pairs

H₂SO₄ and Mg₂Si reaction has the following conjugate pairs,

• HSO₄^– is H₂SO₄’s conjugate base.
• Si^4- is SiH₄‘s conjugate base.

7. H₂SO₄ and Mg₂Si intermolecular forces

H₂SO₄ and Mg₂Si reaction has the following intermolecular forces,

Molecule	Intermolecular forces
H2SO4	Dipole-dipole, hydrogen bond, Van der Waal’s
Mg2Si	Complex ionic bond, metallic bond
SiH4	Covalent bond
MgSO4	Ionic bond

8. H₂SO₄ + Mg₂Si reaction enthalpy

The reaction enthalpy of H₂SO₄ + Mg₂Si is -860. 49 KJ/ mol.

Compound	Moles	Enthalpy of formation, ΔH0f (KJ/mol)
H2SO4	2	-814
Mg2Si	1	-21.20
SiH4	1	34.31
MgSO4	2	-1272

• The following formula is used to compute a reaction’s standard enthalpy,
• The formula is, ΔH⁰_{f (reaction)} = ΣΔH⁰_{f (product)} – ΣΔH⁰_{f (reactants)}
• Thus, enthalpy change = [2*(-1272) + 1*(34.31)] – [2*(-814) + 1*(-21.20)] KJ/mol= -860.49 KJ/mol

9. Is H₂SO₄ + Mg₂Si a buffer solution

H₂SO₄ + Mg₂Si will not create a buffer solution as strong acid H₂SO₄ is present.

10. Is H₂SO₄ + Mg₂Si a complete reaction

H₂SO₄ and Mg₂Si reaction is complete because it results in Silane and Magnesium sulfate, two stable molecules.

11. Is H₂SO₄ + Mg₂Si an exothermic or endothermic reaction

H₂SO₄ and Mg₂Si reaction is exothermic because it generates heat in the environment while creating the result.

12. Is H₂SO₄ + Mg₂Si a redox reaction

H₂SO₄ and Mg₂Si reaction is redox in nature due to the change in silicon ions’ and hydrogen ions’ oxidation states on the reactant and product sides.

13. Is H₂SO₄ + Mg₂Si a precipitation reaction

H₂SO₄ + Mg₂Si reaction is not a precipitation process since no precipitate is produced.

14. Is H₂SO₄ + Mg₂Si a reversible or irreversible reaction

H₂SO₄ and Mg₂Si reaction is an irreversible reaction due to the fact that the products produced do not revert to the reactants under the same conditions.

15. Is H₂SO₄ + Mg₂Si a displacement reaction

Double displacement occurs when H₂SO₄ and Mg₂Si react. Sulfate ions are removed from the H₂SO₄ molecules and silicon ions from the Mg₂Si molecule to create Silane and Magnesium sulfate.

Conclusion

Silane and magnesium sulfate, employed in both commercial and scientific settings, were synthesized by mixing H₂SO₄ and Mg₂Si. Silane is a component of fiberglass that enhances its electrical and mechanical qualities. Magnesium sulfate is used to control viscosity in liquid soaps and detergents.