Laurie Lee Chemistry: Acids and Bases Run-Down

Basic Info:
Acids- feel sticky, taste sour, change litmus red, corrosive to metals, have a pH of 0-6.9
Bases- feel slippery, taste bitter, change litmus blue, have a pH of 7.1-14

Types:
There are two types of acids and bases that we are studying this unit: Arrhenius, and Bronsted-Lowry.

Arrhenius- Arrhenius acids form hydrogen ions in aqueous solution and Arrhenius bases form hydroxide ions (we learned about these a little in the Chemical Reactions unit)

Arrhenius Video

Bronsted-Lowry- acid is defined as anything that releases H1+ ions; a base is defined as anything that accepts H1+ ions (this is new to this unit)

Bronsted-Lowry acids and bases have conjugate acid and base pairs where the proton donors and acceptors are paired together

The CH3COOH is the proton donor and the CH3COO- is the proton acceptor

Bronsted-Lowry Video

Acidic and Basic:

We can determine if a solution is acidic or basic by knowing its concentration of [H+] and [OH-]

[H+]>[OH-] shows that the solution is acidic
[H+]<[OH-] shows that the solution is basic
Temperature does not affect [H+] or [OH-]
Water can act as both acid or base so it is called amphoteric

Calculating pH, pOH, [H+] and [OH-]

There are a few formulas that help with calculating these values.

If you are given the pH of a solution and you are trying to find the [H+] use the formula 10^-pH
If you are given the [H+] and are trying to find the pH use the formula -log[H+]
If you are given the pH and are trying to find the pOH use formula 14-pH
If you are given the [H+] and are trying to get to [OH-] use the formula (1x10^-14)/[H+]

The rest of the calculations (like the inverses) are shown here in this cool flow chart.