The solubility-product constant for barium permanganate, \(\mathrm{Ba}\left(\mathrm{MnO}_{4}\right)_{2}\), is \(2.5 \times 10^{-10}\). Assume that solid \(\mathrm{Ba}\left(\mathrm{MnO}_{4}\right)_{2}\) is in equilibrium with a solution of \(\mathrm{KMnO}_{4}\). What concentration of \(\mathrm{KMnO}_{4}\) is required to establish a concentration of $2.0 \times 10^{-8} \mathrm{M}\( for the \)\mathrm{Ba}^{2+}$ ion in solution?

Short Answer

Expert verified
The required concentration of \(\mathrm{KMnO}_{4}\) to establish a concentration of \(2.0 \times 10^{-8} \mathrm{M}\) for the \(\mathrm{Ba}^{2+}\) ion in the solution is \(7.94 \times 10^{-2} \ \mathrm{M}\).

Step by step solution

01

(Write the chemical equation)

The dissolution of barium permanganate in water can be represented by the following equation: \[ \mathrm{Ba}\left(\mathrm{MnO}_{4}\right)_{2}(s) \rightleftharpoons \mathrm{Ba}^{2+}(aq) + 2\mathrm{MnO}_{4}^{-}(aq) \]
02

(Write the equilibrium constant expression)

The solubility-product constant expression (Ksp) for this reaction is given by: \[ K_{sp} = [\mathrm{Ba}^{2+}][\mathrm{MnO}_{4}^{-}]^{2} \] #Step 2: Use the given \(\mathrm{Ba}^{2+}\) concentration to find the \(\mathrm{MnO}_{4}^{-}\) concentration#
03

(Substitute the given concentration into the equation)

We are given the concentration of \(\mathrm{Ba}^{2+}\) as \(2.0 \times 10^{-8}\ \mathrm{M}\) and the Ksp as \(2.5 \times 10^{-10}\). Hence, we substitute these values into the equation to find the \(\mathrm{MnO}_{4}^{-}\) concentration: \[ 2.5 \times 10^{-10} = (2.0 \times 10^{-8})[\mathrm{MnO}_{4}^{-}]^{2} \]
04

(Calculate the concentration of \(\mathrm{MnO}_{4}^{-}\))

To find the \(\mathrm{MnO}_{4}^{-}\) concentration, we solve for it in the equation: \[ [\mathrm{MnO}_{4}^{-}]^{2} = \frac{1.25 \times 10^{-10}}{2.0 \times 10^{-8}} \] \[ [\mathrm{MnO}_{4}^{-}] = \sqrt{6.25 \times 10^{-3}} \] \[ [\mathrm{MnO}_{4}^{-}] = 7.94 \times 10^{-2} \ \mathrm{M} \] #Step 3: Determine the concentration of \(\mathrm{KMnO}_{4}\) to produce the required \(\mathrm{MnO}_{4}^{-}\) concentration#
05

(Write the reaction of \(\mathrm{KMnO}_{4}\) dissociation)

The dissociation of \(\mathrm{KMnO}_{4}\) in water can be represented as: \[ \mathrm{KMnO}_{4}(s) \rightleftharpoons \mathrm{K}^{+}(aq) + \mathrm{MnO}_{4}^{-}(aq) \]
06

(Determine the required concentration of \(\mathrm{KMnO}_{4}\))

Since the dissociation of one mole of \(\mathrm{KMnO}_{4}\) produces one mole of \(\mathrm{MnO}_{4}^{-}\), in this case, the concentration of \(\mathrm{KMnO}_{4}\) will be equal to the concentration of \(\mathrm{MnO}_{4}^{-}\): \[ [\mathrm{KMnO}_{4}] = [\mathrm{MnO}_{4}^{-}] \] Therefore, the required concentration of \(\mathrm{KMnO}_{4}\) is: \[ [\mathrm{KMnO}_{4}] = 7.94 \times 10^{-2} \ \mathrm{M} \]

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with Vaia!

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Consider the equilibrium $$ \mathrm{B}(a q)+\mathrm{H}_{2} \mathrm{O}(l) \rightleftharpoons \mathrm{HB}^{+}(a q)+\mathrm{OH}^{-}(a q) $$ Suppose that a salt of \(\mathrm{HB}^{+}(a q)\) is added to a solution of \(\mathrm{B}(a q)\) at equilibrium. (a) Will the equilibrium constant for the reaction increase, decrease, or stay the same? (b) Will the concentration of \(\mathrm{B}(a q)\) increase, decrease, or stay the same? (c) Will the pH of the solution increase, decrease, or stay the same?

Mathematically prove that the \(\mathrm{pH}\) at the halfway point of a titration of a weak acid with a strong base (where the volume of added base is half of that needed to reach the equivalence point) is equal to $\mathrm{p} K_{a}$ for the acid.

A 20.0-mL sample of \(0.150 \mathrm{MKOH}\) is titrated with \(0.125 \mathrm{M}\) \(\mathrm{HClO}_{4}\) solution. Calculate the pH after the following volumes of acid have been added: $(\mathbf{a}) 20.0 \mathrm{~mL},(\mathbf{b}) 23.0 \mathrm{~mL},\( (c) \)24.0 \mathrm{~mL}\( (d) \)25.0 \mathrm{~mL},\( (e) \)30.0 \mathrm{~mL}$.

Using the value of \(K_{s p}\) for \(\mathrm{Ag}_{2} \mathrm{~S}, K_{a 1}\) and \(\mathrm{K}_{a 2}\) for \(\mathrm{H}_{2} \mathrm{~S},\) and $K_{f}=1.1 \times 10^{5}\( for \)\mathrm{AgCl}_{2}^{-},$ calculate the equilibrium constant for the following reaction: $$ \mathrm{Ag}_{2} \mathrm{~S}(s)+4 \mathrm{Cl}^{-}(a q)+2 \mathrm{H}^{+}(a q) \rightleftharpoons 2 \mathrm{AgCl}_{2}^{-}(a q)+\mathrm{H}_{2} \mathrm{~S}(a q) $$

A buffer contains 0.20 mol of acetic acid and 0.25 mol of sodium acetate in \(2.50 \mathrm{~L}\). (a) What is the pH of this buffer? (b) What is the pH of the buffer after the addition of 0.05 mol of \(\mathrm{NaOH}\) ? (c) What is the pH of the buffer after the addition of \(0.05 \mathrm{~mol}\) of \(\mathrm{HCl}\) ?

See all solutions

Recommended explanations on Chemistry Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.

Sign-up for free