🧪 pH Scale & Acid-Base Simulator
Acids & BasesWhat's happening? Strong acid: pH = -log[H⁺]. Weak acid: pH = ½(pKa - log C). Strong acids fully dissociate, weak acids only partially. Same concentration gives different pH!
Acids/bases: 10-12 questions every year.
JEE tests pH, buffers, titration, salt hydrolysis. Key: pH = -log[H+].
Key formulas
pH Scale & Acid-Base Formulas
pH
pH = -log[H+]
Strong acid: [H+] = concentration
Weak acid
pH = 1/2(pKa - log C)
When C >> dissociation
Buffer
pH = pKa + log([A-]/[HA])
Henderson-Hasselbalch
pOH
pH + pOH = 14
At 25C
Step-by-step problem solving
How to solve chemistry problems in JEE
- Identify acid/base type
- Strong: [H+] = C directly
- Weak: pH = 1/2(pKa - log C)
- Salts: check hydrolysis
Common JEE mistakes
What students get wrong
Wrong weak acid formula
Don't use -log C for weak acids
Dilution ignored
Recalculate concentration after mixing
pH vs pOH
pH + pOH = 14 at 25C
Buffer sign
pH = pKa + log([base]/[acid])
FAQs
pH Scale & Acid-Base Questions
Salt acidic or basic?
Strong+strong: neutral. Strong base+weak acid: basic. Weak base+strong acid: acidic.
When pH = 1/2(pKa-log C)?
When C >> 100*Ka (dissociation < 5%)
Equivalence point pH?
Strong-strong: 7. Weak-strong: >7. Strong-weak: <7
Dilution effect?
More dissociation but [H+] increases slightly