chemistry unit 9

Acids: 

• Taste sour

• React with metals

• Turn blue litmus paper red

• pH: <7

• A substance that produces H+ ions in water (HCl> H+ + Cl)

Strong acids- pH 0-3

Weak acids- pH >3>7

Ex

• Soda: pH 3

• Milk: pH 6.5

• Lemon juice: pH 2-3

Bases

• Taste bitter

• Slippery to the touch 

• Turns red litmus paper blue

• pH: >7

• A substance that produces OH- (hydroxide) ions in water (NaOH> Na+ + OH-)

Strong bases- pH 13-14

Weak bases- >7>13

Ex: 

• Soap: pH 9

• Bleach: pH 8-13

• Drain cleaners pH: 11-14

Neutral, H2O> H+ + OH-

• Equal concentrations of H+ + OH-

Chemist use to logarithms to express pH (measure of how acidic or basic a solution is)

pH scale: 0-14

Bc pH uses logs each # represents a 10 fold change

• Ex: something with a pH of 5 os 10x more acidic than something with a pH of 6

Equations: 

1. pH+pOH= 14

2. pH=-log [H+]

3. [H+] x [OH-]= 1x10-14

4. 10-pH= [H+]