ch 14a-c Flashcards
(56 cards)
What is the Arrhenius definition of an acid?
A substance that produces H+ ions in aqueous solutions.
What is the Arrhenius definition of a base?
A substance that produces OH- ions in aqueous solutions.
What is the Brønsted-Lowry definition of an acid?
A substance that donates H+ ions.
What is the Brønsted-Lowry definition of a base?
A substance that accepts H+ ions.
What are strong acids?
Acids that completely ionize in solution.
What is the acid ionization constant (Ka)?
A value used to compare the strength of weak acids, defined like an equilibrium constant.
What is the pH of a solution?
The negative logarithm of the hydronium ion concentration, pH = -log[H3O+].
What is the relationship between pH and acidity?
Acidic solutions have pH < 7, and basic solutions have pH > 7.
What is pKa?
The negative logarithm of the acid ionization constant, Ka, indicating the strength of an acid.
How can pKa predict the relative concentration of acid and conjugate base?
If pH > pKa, [A-] > [HA]; if pH < pKa, [A-] < [HA].
What are polyprotic acids?
Acids that have more than one acidic hydrogen, like H2SO3 (diprotic) or H3PO4 (triprotic).
How does bond polarity affect acid strength in binary acids?
Higher bond polarity often increases acid strength in binary acids (e.g., HCl is stronger than HF).
What are strong bases?
Bases that completely ionize in solution.
What is the base ionization constant (Kb)?
A constant used to measure the strength of weak bases.
How are Ka and Kb related?
For a conjugate acid-base pair, pKa + pKb = 14.
How do you find the pH of a strong base solution?
Calculate [OH-] and use pH = 14 - pOH.
What determines if an anion will act as a base?
Anions of weak acids are weak bases; anions of strong acids are generally pH-neutral.
How can you classify a salt solution as acidic, basic, or neutral?
Compare the Ka of the cation and the Kb of the anion; the ion with the larger value determines the pH.
What are the six common strong acids?
Hydrochloric acid (HCl), hydrobromic acid (HBr), hydroiodic acid (HI), nitric acid (HNO3), sulfuric acid (H2SO4), and perchloric acid (HClO4).
Why are these acids considered strong?
They completely ionize in water, releasing H+ ions fully in solution.
What is the formula for hydrochloric acid?
HCl
What is the formula for sulfuric acid?
H2SO4
What is unique about sulfuric acid (H2SO4) as a strong acid?
Only the first ionization (H2SO4 → H+ + HSO4-) is strong; the second ionization (HSO4- → H+ + SO4^2-) is weak.
What are the six common strong bases?
Lithium hydroxide (LiOH), sodium hydroxide (NaOH), potassium hydroxide (KOH), calcium hydroxide (Ca(OH)2), strontium hydroxide (Sr(OH)2), and barium hydroxide (Ba(OH)2).
