1)Why benzoic acid is soluble in NaOH?

2)Why HCl is insoluble in titration of benzoic acid and NaOH?

Benzoic is soluble in a solution of NaOH because the base forms the sodium salt with the acid to form sodium benzoate. The sodium salt is soluble.
The second part of your question isn't clear. Are you titrating the sodium salt? And HCl is soluble in most anything.

1) Well, it's a classic case of "opposites attract." Benzoic acid and NaOH are like long-lost lovers - they just can't resist each other! When you mix them together, NaOH swoops in and snatches up that acid, forming the irresistible duo, sodium benzoate. And just like any good couple, they're soluble in each other's company!

2) Ah, HCl, the lone wolf of the acid world. It's like the grumpy old man who refuses to join the party. When benzoic acid and NaOH are having their titration shindig, HCl decides it's too fancy for its taste and chooses to stay insoluble. I guess you could say it's just not in the mood for a sodium salt dance-off. It prefers to keep its sour, dissociative personality all to itself!

1) Benzoic acid (C7H6O2) is soluble in NaOH (sodium hydroxide) because it undergoes neutralization reaction with the base to form sodium benzoate, which is a water-soluble salt. In this reaction, the sodium hydroxide reacts with the benzoic acid to produce water (H2O) and sodium benzoate (C7H5NaO2). The sodium benzoate is soluble in water due to the presence of the sodium ion (Na+), which stabilizes the compound through its hydration.

2) It seems like you might be asking why hydrochloric acid (HCl) is insoluble in the titration of benzoic acid and sodium hydroxide. However, hydrochloric acid is actually highly soluble in water and any aqueous solution, including the titration mixture. It completely dissociates into H+ and Cl- ions in solution.

If you meant to ask why benzoic acid is not soluble in hydrochloric acid during the titration, the reason is that hydrochloric acid is a stronger acid than benzoic acid. When a stronger acid (HCl) reacts with a weaker acid (benzoic acid) in a titration, the stronger acid will dominate the reaction, and the weaker acid will not readily dissolve or react with the stronger acid. Therefore, benzoic acid remains insoluble in hydrochloric acid during the titration process.

1) The solubility of benzoic acid in NaOH can be explained by understanding the reaction that takes place between the acid and the base. When benzoic acid (a weak acid) is dissolved in a solution of NaOH (a strong base), it undergoes a neutralization reaction. The OH^- ions from NaOH react with the H+ ions from benzoic acid to form water (H2O).

The reaction can be represented as follows:
C6H5COOH (benzoic acid) + NaOH (sodium hydroxide) → C6H5COONa (sodium benzoate) + H2O (water)

Sodium benzoate, the product of this reaction, is a water-soluble salt. Therefore, it can dissolve in the solution of NaOH, resulting in the overall solubility of benzoic acid in NaOH.

2) The insolubility of HCl (hydrochloric acid) in the titration of benzoic acid and NaOH can be explained by two reasons.

First, HCl is a strong acid, and its molecules are completely ionized in water to form H+ ions and Cl^- ions. In the presence of a strong base like NaOH, the OH^- ions from NaOH react with the H+ ions from HCl to form water (H2O). This reaction between the acid and the base is more favorable than the reaction between benzoic acid and NaOH.

Secondly, the chloride ions (Cl^-) formed from HCl are much more soluble in water compared to benzoic acid, sodium benzoate, or any other intermediate compounds that may form during the titration. As a result, the chloride ions remain dissolved in the solution and do not contribute to any insolubility issues during the titration.

Overall, the higher solubility of HCl and the preference for the reaction between HCl and NaOH lead to its insolubility in the specific scenario of titrating benzoic acid and NaOH.