Acid/Base Theories
True or False: An Arrhenius acid forms H+ ions in a solution.
True
True or False: Acids are bitter, and Bases are sour.
False. Bases are bitter, and acids are sour.
What is the difference between an acid and its conjugate base?
A conjugate base has one less H+.
Are organic acids weak or strong?
Example: CH3COOH
Weak
pH + pOH = ?
(at 25 *C)
14
True or False: A Brønsted-Lowry base is a donor of protons.
False
When tested with phenolphthalein, what color does a basic solution turn?
The solution turns pink.
Provide the conjugate base of acetic acid, CH3COOH.
CH3COO-
True or False: Strong acids/bases dissociate fully.
True
True or False: An acidic solution has a large concentration of [H+] and a high pH.
False. An acidic solution has a low pH.
What does mixing an Arrhenius acid and base produce?
Salt and water
When a solution is basic, the litmus paper turns ____. When a solution is acidic, the litmus paper turns ____.
basic = blue, acidic = pink
Provide the conjugate acid/base pair of NH3 (a base).
NH3 / NH4+
How many strong acids are diprotic? Name the acid(s).
1, H2SO4
What is the formula to find pH using [H+]?
pH = -log([H+])
What does it mean for a substance to be amphoteric? Name an example.
An amphoteric substance can act as an acid or a base.
Example: H2O can donate H+ or accept it.
A student titrates a solution of NaOH with an excess of HCl. The student drops some of the resulting solution onto litmus paper, which turns pink. Is the solution acidic or basic?
It is acidic.
Which of the following is a conjugate acid/base pair?
H2SO4 / SO4 2-
H3PO4 / PO4 3-
HNO3 / NO3 -
HBr / Cl-
HNO3 / NO3 -
Give an example of a weak base (name and formula).
answers vary — one example is ammonium hydroxide, NH4OH.
What is a buffer solution?
A buffer solution resists changes in pH when an acid or base is added.
Which theory states that acids and bases form conjugate bases and acids?
The Bronsted-Lowry theory.
When equimolar solutions of a strong acid and base are combined, the resulting solution has a pH of _____.
7
Complete the chemical reaction below:
NaOH + CH3COOH ⇌ __________ + H2O
NaCH3COO
Name all of the strong acids.
HCl, HBr, HI, H2SO4, HNO3, HClO4
What is the pOH of a 0.1 L 0.1M HCl solution?
13
pH = -log([H+]) = -log(0.1) = 1
14 - pH = pOH = 13