In an aqueous solution of lithium chloride (LiCl), the ions present in solution are lithium cations (Li+) and chloride anions (Cl-), and the water molecules (H2O).
Lithium chloride is an ionic salt, and therefore, fully dissociates or ionizes upon dissolution in water. From the chemical formula of lithium chloride, we can say that 1 lithium ion (positively-charged) only needs 1 chloride ion (negatively charged) to form the salt. Thus, upon dissociation of 1 molecule of LiCl, only 1 lithium ion, and 1 chloride ion form.
Water is a molecule formed by covalent bonds and <u>generally</u>, does not dissociate to form ions. However, if we consider the very minor contribution of the dissociation of water, hydroxide (OH-) ions and hydronium (H3O+) ions will also be present. However for water, very few molecules, only 1 in 550 million, are dissociated at any given time. Thus, we can consider the presence of the OH- and H3O+ ions to be negligible and just identify the molecular undissociated form of water to be present.
We consider the given reaction H2SO4 + 2 NaOH -> Na2SO4 + 2H2O as applies to an acid-base titration.
moles NaOH = c · V = 0.2767 mmol/mL · 25.34 mL = 7.011578 mmol
moles H2SO4 = 7.011578 mmol NaOH · 1 mmol H2SO4 / 2 mmol NaOH
= 3.505789 mmol
Hence
[H2SO4]= n/V = 3.505789 mmol / 39.54 mL = 0.08866 M
The answer to this question is [H2SO4] = 0.08866 M
