Lesson 4: pH, Acids, Bases, And Buffers Flashcards
(15 cards)
What is the pH scale?
A numerical scale (0-14) that measures how acidic or basic a substance is.
What pH values indicate acids, bases, and neutral substances?
Acids:** pH < 7
- Neutral: pH = 7
- Bases: pH > 7
How can pH be measured?
Using indicators (e.g., litmus paper, phenolphthalein) or a pH meter (measures electrical conductivity).
What color does litmus paper turn in acids and bases?
Acids:** Red
- Bases: Blue
How do acids behave in water?
They dissociate to release H⁺ ions (protons).
What is a key feature of acid formulas?
Most acids start with H (e.g., HCl, H₂SO₄).
Give examples of common acids.
HCL** hydrochloric acid)
- H₂SO₄ (sulfuric acid)
- HNO₃ (nitric acid)
- CH₃COOH (acetic acid)
What are the rules for naming acids?
No oxygen (-ide anion):** Add hydro- and change -ide to -ic acid (e.g., HF → Hydrofluoric acid).
- With oxygen (-ate anion): Change -ate to -ic acid (e.g., H₂CO₃ → Carbonic acid).
- With oxygen (-ite anion): Change -ite to -ous acid (e.g., H₂SO₃ → Sulfurous acid).
How do bases behave in water?
How do bases behave in water?
A: They dissociate to release OH⁻ ions (hydroxide).
What is a key feature of base formulas?
Most bases end with OH (e.g., NaOH, KOH).
Why can acids and bases conduct electricity?
They release ions in solution, making them electrolytes.
What happens when an acid and base mix?
Neutralization** occurs:
H⁺ (aq) + OH⁻ (aq) → H₂O (l)
What does neutralization produce?
Water (H₂O) and a salt.
What is a buffer?
A solution that resists changes in pH by absorbing or releasing H⁺ or OH⁻ ions.
Why are buffers important in the body?
They maintain stable pH levels in blood and cells (e.g., carbonic acid-bicarbonate buffer in blood).
