Which of the following can act as buffer solutions? 0.1 M HC_2H_3O_2/0.1 1 M NaC

Question

Which of the following can act as buffer solutions? 0.1 M HC_2H_3O_2/0.1 1 M NaC_2H_3O_2 0.1 M NH_3/0.1 M NH_4 CI 0.1 M HNO_3/0.1 M NaNO-3 0.1 M H_2SO_3/0.1 M NaHSO_3 0.1 M KHSO_4/0.1 M H_2SO_4 I), II), and III) II), III) and IV) III) and IV) I), II) and IV) III), IV) and V) Phenol red indicator changes from yellow to red in the pH range from 6.6 to 8.0. State what color the indicator will assume in the following solution: 0.20M KOH A) red B) yellow C) red-yellow mixture D) orange E) The indicator would be colorless. What factor governs the selection of an indicator for a neutralization titration? A) the final volume of the solution B) the volume of titrant C) the molarity of the standard solution D) the pH at the stoichiometric (equivalence) point the solubility of the indicator For the following titration, determine whether the solution at the equivalence point is acidic, basic or neutral and why: HCl is titrated with NH_3(aq) A) acidic because of hydrolysis of NH_4^+ B) basic because of hydrolysis of NH_3 C) acidic because of hydrolysis of Cl^- D) acidic because of hydrolysis of HCl E) neutral salt of strong acid and strong base Why do we avoid titrating ammonia with acetic acid? A) The change in pH near the equivalence point is not large enough to be accurately detected. B) There is no known indicator which changes color at the right pH. C) The reaction is slow. D) There is not enough difference between the ionization constants of ammonia and acetic acid. E) Ammonia does not react with acetic acid. The solubility of copper(II) iodate Cu(IO_3)_2, is reported as 0.12 g per 100 mL. What is the solubility product constant, Ksp, for this salt? The MM for Cu(IO_3)_2 is 413.35g/mol. A) 9.8 times 10^-8 B) 8.6 times 10^-7 C) 7.3 times 10^-6 D) 6.4 times 10^-5 E) 1.2 times 10^-4

Explanation / Answer

(7) A buffer is the the homogeneous mixture of weak acid or weak base and its salt with strong base or strong acid.

So,

(C) I, II and IV act as buffer solutions.

I. weak acetic acid and its salt of strong base, sodium acetate

II. Weak base, ammonia and its with strong acid, Ammonium chloride

IV. weak acid, sulphurous acid and its salt strong base, sodiumbisulphite

(8) In basic medium it is in red color. Since pH of basic solution is greater than 7.0

(a) red

(9)

(D) th epH at the equivalent point

(10)

(A) acidic because of hydrolysis of NH4+

(11)

(A)

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.