Li2SiO3 is the basic oxide of alkali metals so it can react with strong acids like hydrochloric. Let us see the mechanism and reaction pathway of the HCl and Li2SiO3.
Lithium silicate or lithium metasilicate is the basic salt and the central Li is in +1 oxidation state and the Si-O bond is stronger due to π bond formation. The more concentrated form of HCl is required for the reaction with lithium silicate and there is no need for any catalyst or outer temperature.
To find the amount of silicon in lithium silicate we can perform a titration reaction with strong hydrochloric acid. In this article, we will learn more about reactions like enthalpy, redox reaction, intermolecular force, conjugate pairs, etc with an explanation in the following part of the article.
1. What is the product of HCl and Li2SiO3?
Lithium chloride along with metasilic acid is formed when HCl and Li2SiO3 are subject to reaction but metasilic acid also dissociates into water and silicon dioxide.
2. What type of reaction is HCl + Li2SiO3?
The reaction HCl + Li2SiO3 is acid-base reactions and it is one type of redox reaction and displacement reaction, as the latter is basic in nature and the former is strongly acidic. In this reaction, several elements are oxidized and reduced like Li, Si, and Cl.
3. How to balance HCl + Li2SiO3?
HCl + Li2SiO3 = LiCl + H2O + SiO2 this reaction is not balanced yet because the L.H.S of the reaction is not equal to the R.H.S., so we have to balance the equation in a few steps·
- Step 1 – Labelling all the reactants and products by the required number of alphabets
- We labeled all the molecules in the part of the reactant as well as the product side by A, B, C, D, and E as there is a total of five molecules present unbalanced. Now the reaction reduces to, A HCl + B Li2SiO3 = C LiCl + D SiO2 + E H2
- Step 2 – Equating all the Coefficients for all the same type of elements by rearranging them
- Arranging all the same elements by their stoichiometric proportion and coefficients we get,
- H = A = 2E, Cl = A = C, Li = 2B = C, Si = B = D, O = 3B = 2D = E
- Step 3 – Using Gaussian elimination to determine the coefficient values
- Using the Gaussian elimination and equating all the equations we get, A = 2, B = 1, C = 2, D = 1
- Step 4- now write the whole equation in the balanced form
- The overall balanced equation will be, 2HCl + Li2SiO3 = 2LiCl + SiO2 + H2O
4. HCl + Li2SiO3 titration
To estimate the quantity of silicon we can perform a titration between Li2SiO3 and HCl
Apparatus used
We need a burette, conical flask, burette holder, volumetric flask, and beakers for this titration.
Titre and titrant
HCl versus Li2SiO2, HCl acts as titrant which is taken in the burette and the molecule to be analyzed is Li2SiO2 which is taken in a conical flask.
Indicator
The whole titration is done in an acidic medium or acidic pH so the best suitable indicator will be phenolphthalein which gives perfect results for this titration at given pH.
Procedure
The burette was filled with standardized HCl and Li2SiO3 was taken in a conical flask along with the respective indicator. HCl is added dropwise to the conical flask and the flask was shaking constantly. After a certain time when the endpoint arrived indicator changes its color and the reaction was done.
We repeat the titration several times for better results and then we estimate the silicon quantity by the formula V1S1 = V2S2.
5. HCl+ Li2SiO3 net ionic equation
In the reaction between HCl + Li2SiO3 several ions are formed and some molecules are dissociated into ions, like chloride, and lithium-ion along with proton but SiO2 cannot be dissociated.
H+ + Cl– + Li+ + SiO3– = Li+ + Cl– + H+ + OH– + SiO2
6. HCl+ Li2SiO3 conjugate pairs
In the reaction HCl + Li2SiO3 Chloride is the conjugate base of strong acid hydrochloric and the conjugate pair of Li2SiO3 is the silicate and the other protonic form of the particular molecule.
- Conjugate pair of HCl = Cl–
- Conjugate pair of Li2SiO3 = Li3SiO32-
7. HCl and Li2SiO3 intermolecular forces
The ionic and electrostatic forces are present in HCl as also dipole interaction and for the Li2SiO3 there are ionic forces along with covalent interaction present. Some H-bonding present in water and for SiO2 there is covalent interaction along with van der waal’s interaction present.
Molecule | Acting force |
HCl | Electrostatic, van der waal’s, dipole interaction |
Li3SiO3 | Ionic, covalent, van der waal’s |
LiCl | Ionic, Strong electrostatic |
SiO2 | Covalent |
H2O | Covalent, H-bonding, electrostatic |
8. HCl + Li2SiO3 reaction enthalpy
For the reaction HCl + Li2SiO3 the reaction enthalpy is, -934.03 KJ/mol which can be obtained by the formula enthalpy of products – enthalpy of reactants, and here the change in enthalpy is negative.
Molecule | Enthalpy (KJ/mol) |
Li2SiO3 | -677 |
HCl | -92.3 |
LiCl | -408.27 |
SiO2 | -911.09 |
H2O | -68 |
of the moelcules
9. Is HCl + Li2SiO3 a buffer solution?
The reaction between HCl + Li2SiO3 gives a buffer solution of silicate ions which can control the pH of the solution as it has both acidic as well as basic characteristics at certain pH.
10. Is HCl + Li2SiO3 a complete reaction?
The reaction between HCl + Li2SiO3 is complete reaction which gives two complete products H2SiO3 and LiCl, further upon full dissociation of H2SiO3 we get water and SiO2 and utilization of the reactants.
11. Is HCl + Li2SiO3 an exothermic or endothermic reaction?
The change of enthalpy for the reaction of HCl + Li2SiO3 indicates it is an exothermic process based on thermodynamics, on the other hand, the reactant released heat in the course of the reaction or we can say δH = HProducts-Hreactans < 0.
12. Is HCl + Li2SiO3 a redox reaction?
Si and Cl get oxidized where Li gets reduced when HCl and Li2SiO3 gets reacted so it is a redox reaction and where oxidation number of several elements are changed.
13. Is HCl + Li2SiO3 a precipitation reaction
The reaction between HCl + Li2SiO3 is a precipitation reaction where lithium silicate precipitated and LiCl can soluble in water and again when Li2SiO3 gets dissociated into water and SiO2, then SiO2 remain insoluble in the reaction medium.
14. Is HCl + Li2SiO3 reversible or irreversible reaction?
The first reaction HCl + Li2SiO3 are irreversible because that reaction proceeds only forward direction but the dissociation of H2SiO3 into H2O and SiO2 is reversible and proceed in both a forward and backward direction.
15. Is HCl + Li2SiO3 displacement reaction?
The above reaction between HCl + Li2SiO3 is a single displacement reaction where Li is displaced and gets attached to Cl.
Conclusion
To estimate the quantity of Si we can use the titration between Li2SiO3 and HCl because Li2SiO3 is the raw form where Si is stored. By this reaction we also estimate the quantity of Li as well. The reaction does not required any catalyst and temperature because it is an exothermic reaction.
Read more facts on HCl:
Hi……I am Biswarup Chandra Dey, I have completed my Master’s in Chemistry from the Central University of Punjab. My area of specialization is Inorganic Chemistry. Chemistry is not all about reading line by line and memorizing, it is a concept to understand in an easy way and here I am sharing with you the concept about chemistry which I learn because knowledge is worth to share it.