Question

he fluoride ion? View Available Hint(s) When a pH probe is inserted into a solution containing the chloride ion it is neutral. What is the pH of a solution containing the fluoride ion? The solution will be weakly acidic The solution will be weakly basic The solution will be strongly basic The solution will be neutral. The solution will be strongly acidic. Submit Part B The Ka of NH4+ is 5.6 × 10−10. The Kb of CN− is 2 × 10−5. The pH of a salt solution of NH4CN would be: View Available Hint(s) The of is . The of is . The pH of a salt solution of would be: Less than 7 because NH4+ is a stronger acid than CN− is a base. Greater than 7 because CN− is a stronger base than NH4+ is an acid Less than 7 because CN− is a stronger base than NH4+ is an acid. Greater than 7 because NH4+ is a stronger acid than CN− is a base. Submit Provide Feedback

Answer 1

Answer:

a. the solution will be weakly basic.

b. Greater than 7 because CN⁻ is a stronger base than NH₄⁺ is an acid.

Explanation:

a. The fluoride ion (F⁻) reacts with water thus:

F⁻ + H₂O → HF + OH⁻

That means that fluoride ions produce OH⁻ ions in solution doing the solution will be weakly basic.

b. The acidic equilibrium of NH₄⁺ is:

NH₄⁺ ⇄ NH₃ + H⁺ with a ka of 5,6x10⁻¹⁰.

The basic equilibrium of CN⁻ is:

CN⁻ + H₂O → HCN + OH⁻ with a kb of 2x10⁻⁵

That means that the production of OH⁻ from CN⁻ is higher than production of H⁺ from NH₄⁺. The CN⁻ is a stronger base than NH₄⁺ is an acid.

Thus, the pH of a salt solution of NH₄CN would be Greater than 7 because CN⁻ is a stronger base than NH₄⁺ is an acid.

I hope ot helps!