CHEM 6C Review

Acid or Base?

100

pH < 7

Acid 

200

pH > 7

Base

300

increases [H₃O⁺] 

Acid

400

increases [OH^-]

Base

500

Will deprotonate in solution 

Acid

Strong or Weak?

100

HCl

Strong Acid

200

NaOH

Strong Base

300

HF

Weak Acid

400

NH₃

Weak Base

500

H₂SO₄

Strong Acid

Identifying Species

100

HCl + NH₃ --> Cl^- + NH₄⁺

^{What is the acid?}

HCl

200

HCl + NH₃ --> Cl^- + NH₄⁺

What is the base?

NH₃

300

HCl + NH₃ --> Cl^- + NH₄⁺

What is the conjugate acid?

NH₄⁺

400

HCl + NH₃ --> Cl^- + NH₄⁺

What is the conjugate base?

Cl^-

500

HCl + NH₃ --> Cl^- + NH₄⁺

What would the resulting pH be?

Acidic (strong acid + weak base --> acidic salt)

Calculating pH

100

What is the equation for pH?

pH = -log [H⁺]

200

What is the pOH?

pOH= -log[OH^-]

300

How to find [H⁺] from pH?

[H⁺] = 10^-pH

400

How to find [OH^-] from pOH?

[OH^-] = 10^-pOH

500

What is the pH of a 0.0235 M HCl solution?

pH = 1.629

Ka and Kb

100

What is the equation for Ka?

Ka = [H3O+][A-]/[HA]

200

What is the equation for pKa?

pKa = -log[Ka]

300

Which is Stronger?

H₂CO₃       Ka = 4.4 * 10^-7 

HF         Ka = 6.6 * 10^-4 

HF

larger Ka

400

Which is stronger 

• CH3CO2H, pKa =4.74

• H2PO4-, Ka = 6.2 * 10^-8

CH3CO2H

500

Which has a stronger conjugate base?

• H3PO4, pKa = 2.12 

• H2CO3, Ka = 4.4 * 10^-7 

H₂CO₃