Table of contents

1. Matter and Measurements4h 31m
2. Atoms and the Periodic Table5h 23m
3. Ionic Compounds2h 18m
4. Molecular Compounds2h 18m
5. Classification & Balancing of Chemical Reactions3h 17m
6. Chemical Reactions & Quantities2h 27m
7. Energy, Rate and Equilibrium3h 46m
8. Gases, Liquids and Solids3h 25m
9. Solutions4h 10m
10. Acids and Bases3h 29m
11. Nuclear Chemistry56m
BONUS: Lab Techniques and Procedures1h 38m
BONUS: Mathematical Operations and Functions47m
12. Introduction to Organic Chemistry1h 34m
13. Alkenes, Alkynes, and Aromatic Compounds2h 12m
14. Compounds with Oxygen or Sulfur1h 6m
15. Aldehydes and Ketones1h 1m
16. Carboxylic Acids and Their Derivatives1h 11m
17. Amines39m
18. Amino Acids and Proteins1h 51m
19. Enzymes1h 37m
20. Carbohydrates1h 41m
21. The Generation of Biochemical Energy2h 8m
22. Carbohydrate Metabolism2h 22m
23. Lipids2h 26m
24. Lipid Metabolism1h 45m
25. Protein and Amino Acid Metabolism1h 37m
26. Nucleic Acids and Protein Synthesis2h 54m

10. Acids and Bases

pH of Strong Acids and Bases

GOB Chemistry

10. Acids and Bases

pH of Strong Acids and Bases

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1:59 minutes

Problem 107a

Textbook Question

Determine each of the following for a 0.050 M KOH solution:
a. [H₃O⁺]

Verified step by step guidance

Step 1: Recognize that KOH is a strong base, meaning it completely dissociates in water. The concentration of OH⁻ ions in the solution will be equal to the concentration of KOH, which is 0.050 M.

Step 2: Use the relationship between the concentrations of H₃O⁺ and OH⁻ in water, which is given by the ion-product constant for water:

K_{w} = [H₃O⁺][OH⁻]. The value of K_{w} at 25°C is 1.0 × 10⁻¹⁴.

Step 3: Rearrange the equation to solve for [H₃O⁺]:

[H₃O⁺] = \frac{K_{w}}{[OH⁻]}

Step 4: Substitute the known values into the equation:

[H₃O⁺] = \frac{1.0 × 10⁻¹⁴}{0.050}

Step 5: Perform the division to calculate [H₃O⁺]. This will give you the hydronium ion concentration in the solution.

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Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

pH and pOH

pH is a measure of the acidity or basicity of a solution, defined as the negative logarithm of the hydronium ion concentration, [H₃O⁺]. pOH, on the other hand, measures the concentration of hydroxide ions, [OH⁻]. In a basic solution like KOH, pH and pOH are related through the equation pH + pOH = 14, which is essential for determining the [H₃O⁺] concentration.

Ionization of Water

Water undergoes autoionization, producing equal concentrations of H₃O⁺ and OH⁻ ions at equilibrium. The ion product constant for water (Kw) at 25°C is 1.0 x 10⁻¹⁴, which means that the product of [H₃O⁺] and [OH⁻] is always constant. This relationship is crucial for calculating the hydronium ion concentration in a KOH solution.

Concentration of KOH

KOH is a strong base that completely dissociates in solution to produce K⁺ and OH⁻ ions. A 0.050 M KOH solution means that the concentration of OH⁻ ions is also 0.050 M. This concentration is used to find the [H₃O⁺] by applying the ion product constant of water, allowing for the determination of the solution's acidity.

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