Acids & Bases Logic Flashcards

What is a buffer?

A buffer is a solution containing relatively large amounts of WEAK ACID AND ITS CONJUGATE BASE

pH = _________________

-log[H3O+] or -log[Ka]

pOH = ________________

-log[OH-]

What is the purpose of a buffer?

To prevent large changes in pH upon the addition of acids or bases

How can we find whether a buffer is acidic or basic?

Calculate the pH using “pH = -log[Ka],” using the Ka of the acid in the equation

What is an indicator?

It is a weak acid or base that has different colors for their conjugate acid and base forms

When an indicator is placed into an acid solution, what happens?

The excess H3O+ causes a shift in the indicators equilibrium

When an indicator is placed into a basic solution, what happens?

The OH- reacts to decrease the [H3O+] and causes a shift in the indicators equilbrium

An indicator is in its CONJUGATE ACID (HIn) form when in _________________ solutions

HIGHLY ACIDIC

An indicator is in its CONJUGATE BASE (In-) form when in _________________ solutions

HIGHLY BASIC

What is the transition point of an indicator?

The half way point where there are equal numbers of molecules and base form, and when [HIn] = [In-]

At the midpoint of an indicator’s pH range, KIn = ___________

10^-pH

Where does the transition point of an indicator occur?

It occurs at the mid-point of the indicator’s pH range

What compounds undergo hydrolysis?

• CB of SA,

• Compounds not from group 1/2

• Salts that are not of a weak acid or base

• Certain metal oxides

Metal oxides produce _______________ when dissolved in water

BASIC solutions

Non-metal oxides produce _________________ when dissolved in water

ACIDIC solutions