Calculate \(\left[\mathrm{OH}^{-}\right]\) for each of the following solutions, and indicate whether the solution is acidic, basic, or neutral: (a) \(\left[\mathrm{H}^{+}\right]=0.0505 \mathrm{M} ;\) (b) \(\left[\mathrm{H}^{+}\right]=2.5 \times 10^{-10} \mathrm{M} ;(\mathrm{c})\) a solution in which \(\left[\mathrm{H}^{+}\right]\) is 1000 times greater than \(\left[\mathrm{OH}^{-}\right] .\)

Short Answer

Expert verified
(a) For [H⁺] = 0.0505 M, [OH⁻] = 1.98 × 10⁻¹³ M and the solution is acidic. (b) For [H⁺] = 2.5 × 10⁻¹⁰ M, [OH⁻] = 4.0 × 10⁻⁵ M and the solution is basic. (c) In a solution where [H⁺] is 1000 times greater than [OH⁻], [OH⁻] = 3.16 × 10⁻⁷ M and the solution is acidic.

Step by step solution

01

Calculate [OH⁻] for part (a)

Given [H⁺] = 0.0505 M, and we know the ion product of water (Kw) is \(1.0 \times 10^{-14}\). Using the Kw equation, we find [OH⁻]: \[1.0 \times 10^{-14} = (0.0505)([OH^-]) \] \[[OH^-] = \frac{1.0 \times 10^{-14}}{0.0505} = 1.98 \times 10^{-13} M\]
02

Determine the nature of solution (a)

Since [OH⁻] < [H⁺], the solution is acidic. #Part (b)#
03

Calculate [OH⁻] for part (b)

Given [H⁺] = 2.5 × 10⁻¹⁰ M Using the Kw equation, we find [OH⁻]: \[1.0 \times 10^{-14} = (2.5 \times 10^{-10})([OH^-]) \] \[[OH^-] = \frac{1.0 \times 10^{-14}}{2.5 \times 10^{-10}} = 4.0 \times 10^{-5} M\]
04

Determine the nature of solution (b)

Since [OH⁻] > [H⁺], the solution is basic. #Part (c)#
05

Setting up an equation to solve for [OH⁻] in part (c)

Let [H⁺] be x, then the given condition is: [H⁺] = 1000 × [OH⁻]. So, x = 1000 × [OH⁻], and we know Kw = [H⁺][OH⁻].
06

Calculate [OH⁻] for part (c)

Using the given condition and Kw equation: \[1.0 \times 10^{-14} = (1000[OH^-])([OH^-])\] \[[OH^-]^2 = \frac{1 \times 10^{-14}}{1000}\] \[[OH^-] = \sqrt{\frac{1 \times 10^{-14}}{1000}} = 3.16 \times 10^{-7}\]
07

Determine the nature of solution (c)

Since [OH⁻] < [H⁺], the solution is acidic.

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

Predict whether aqueous solutions of the following substances are acidic, basic, or neutral: (a) \(\mathrm{AlCl}_{3}\), (b) \(\mathrm{NaBr}\), (c) \(\mathrm{NaClO},(\mathrm{d})\) \(\left[\mathrm{CH}_{3} \mathrm{NH}_{3}\right] \mathrm{NO}_{3},(\mathrm{e}) \mathrm{Na}_{2} \mathrm{SO}_{3}\)

What is the \(\mathrm{pH}\) of a solution that is \(2.5 \times 10^{-9}\) in \(\mathrm{NaOH}\) ? Does your answer make sense? What assumption do we normally make that is not valid in this case?

Calculate \(\left[\mathrm{OH}^{-}\right]\) and \(\mathrm{pH}\) for (a) \(1.5 \times 10^{-3} \mathrm{M} \mathrm{Sr}\left(\mathrm{OH}_{2}\right),\) (b) \(2.250 \mathrm{~g}\) of \(\mathrm{LiOH}\) in \(250.0 \mathrm{~mL}\) of solution, (c) \(1.00 \mathrm{~mL}\) of \(0.175 \mathrm{M} \mathrm{NaOH}\) diluted to \(2.00 \mathrm{~L},\) (d) a solution formed by adding \(5.00 \mathrm{~mL}\) of \(0.105 \quad M \mathrm{KOH}\) to \(15.0 \mathrm{~mL}\) of \(9.5 \times 10^{-2} \mathrm{M} \mathrm{Ca}(\mathrm{OH})_{2}\)

The average \(\mathrm{pH}\) of normal arterial blood is \(7.40 .\) At normal body temperature \(\left(37^{\circ} \mathrm{C}\right), K_{w}=2.4 \times 10^{-14} \cdot\) Calculate \(\left[\mathrm{H}^{+}\right]\) \(\left[\mathrm{OH}^{-}\right],\) and \(\mathrm{pOH}\) for blood at this temperature. $$ \begin{array}{llll} \hline \text { pH } & \text { pOH } & \text { [H }^{+} \text {] } & \text { [OH }^{-} \text {] } & \text { Acidic or basic? } \\ \hline 5.25 & & & \\ & 2.02 & & \\ & & 4.4 \times 10^{-10} M & & \\ & & & 8.5 \times 10^{-2} M & \\ \hline \end{array} $$

Label each of the following as being a strong base, a weak base, or a species with negligible basicity. In each case write the formula of its conjugate acid, and indicate whether the conjugate acid is a strong acid, a weak acid, or a species with negligible acidity: (a) \(\mathrm{CH}_{3} \mathrm{COO}^{-},\) (b) \(\mathrm{HCO}_{3}^{-}, (\mathrm{c}) \mathrm{O}^{2-}, (\mathrm{d}) \mathrm{Cl}^{-} ,(\mathrm{e}) \mathrm{NH}_{3}\)

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