IB Chemistry on Acid Base Indicators and Salt Hydrolysis

Acid Base Indicators

Indicators • Organic dye of weak acid/weak base with pKa/pKb value • Detect equivalence point in titration • HIn as indicator have 2 different colours in acidic/alkaline medium

HIn ↔ H+ + In-

(red) (blue)

HIn ↔ H+ + In- • (H+ ions ↑) - Equilibrium shift to left • More [HIn ] → red , [HIn] > [In-]

HIn ↔ H+ + In- (H+ ions ↓) - Equilibrium shift to right More [In- ] → blue, [In-] > [HIn]

Indicator pKa pH range

Colour Acid

Colour Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Bromophenol Blue 4.10 3.0- 4.6 Yellow Blue

Bromocresol Green 4.90 3.8- 5.4 Yellow Blue

Methyl Red 5.00 4.8- 6.0 Red Yellow

Bromothymol Blue 7.30 6.0- 7.6 Yellow Blue

Phenol Red 8.00 6.6- 8.2 Yellow Red

Phenolphthalein 9.50 8.2- 10.0

Colourless Pink

acid base

Presence of base, OH- Presence of acid, H+

HIn ↔ H+ + In-

(red) (blue)

Ka = (H+)(In-) (HIn)

(HIn) = (H+) (In-) Ka

H+ = Ka

-lgH+ = -lg Ka

pH = pKa

↔ ↔ Presence of acid, H+ Presence of base, OH-

[HIn] > [In-] RED

[In-] > [HIn] BLUE

HIn = In- → pH = pKa → Two colours red/blue will have equal conc, • Indicator have colour in bet red and blue (start to change colour)

[HIn] = [In-] Equivalence Point

Start to change colour

HIn ↔H+ + In- HIn In-

[HIn] = [In-] RED + BlUE

x log

both sides

Click here on indicator notes from chem guide

Click here on detail acid/base notes

• Indicators change colour at its pKa but it cannot be detected by our eyes • pH range – Indicator changes colour over a range of pH • Methyl orange, pKa is 3.46 but change colour in the range of pH (3.2-4.4) • pH range (pH = pKa ±1) seen by our eye • Indicator must only change colour at equivalence point • End point of indicator must correspond/coincide with equivalence point • Colour change must occur rapidly at equivalence point • Indicator usually change colour over a region of 2 pH units centered on pKa

Indicator change colour at its pKa

Indicator do not change colour at pH 7

Acid Base Indicators

Indicator pKa pH range

Colour Acid

Colour Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Bromophenol Blue 4.10 3.0- 4.6 Yellow Blue

Bromocresol Green 4.90 3.8- 5.4 Yellow Blue

Methyl Red 5.00 4.8- 6.0 Red Yellow

Bromothymol Blue 7.30 6.0- 7.6 Yellow Blue

Phenol Red 8.00 6.6- 8.2 Yellow Pink

Phenolphthalein 9.50 8.2- 10.0 Colourless Pink Indicator pKa pH range

Colour

Acid

Colour Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

pH range

(3.2 – 4.4)

pH 1 pH 4.4 3.46

pH range – changes colour over a range of pH

Acid Base

Methyl Orange Indicator

Indicator pKa pH range

Colour Acid

Colour Base

Phenol Red 8.00 6.6- 8.2 Yellow Pink

Base

Phenol Red

pH 1 pH 6.6 pH 8.2 pH 14 pH range

(6.6 – 8.0)

Acid

8

Indicator changes colour at its pKa

Indicator do not change colour at pH 7

pH 14 pH 3.2

pH range – changes colour over a range of pH

Equivalence Point End Point

Amt of acid = Amt base (Neutralization)

Indicator change colour

Indicator Colour Acid

pKa pH range

Colour Base

HIn RED 4.5 3.5 – 5.5 BLUE

Acid Base Indicators

pH 1 pH 3.5 4.5

pH 5.5 pH 14

HIn Indicator

Indicator change

colour at pKa

Range of pH indicator

change colour

HIn ↔ HIn ↔H+ + In- ↔ In-

[HIn] = [In-] RED + BLUE

pH = 4.5 → pKa of HIn, indicator change colour (end point) from red to blue • Red turn blue but cannot be detected by our eyes • Indicator change colour over a region of 2 pH units centerd on pKa

HIn ↔ H+ + In-

(red) (Blue)

Ka = (H+)(In-) (HIn) (H+) = (HIn) Ka (In-)

H+ = Ka

-lgH+ = -lg Ka

pH = pKa

pH = 4.5 (pKa of indicator)

[HIn] = 10 [In-] 1 [HIn] > [In-] by 10x

Ka = (H+)(In-) (HIn) H+ = Ka x (HIn) = Ka x 10 (In-) H+ = 10Ka

-lgH+ = -lg 10 - lgKa

pH = -1 + pKa

pH = -1 + 4.5 pH = 3.5

[HIn] =10 [In-] 1

[HIn] = 1 [In-] 10 [In-] > [HIn] by 10x

Ka = (H+)(In-) (HIn) H+ = Ka x (HIn) = Ka x 1/10 (In-) H+ = Ka /10

-lgH+ = - lgKa - lg10-1

pH = pKa + 1

pH = 4.5 + 1 = 5.5 pH = 5.5,

[HIn] = 1 [In-] 10

[HIn] = 1 [In-] 1

pH ≤ 3.5, eye detects it RED pH ≥ 5.5, eye detects it BLUE

Conc [Hin] > [In-] by 10x Conc [Hin] < [In-] by 10x

[HIn] = 1 [In-] 1 [HIn] = [In-]

Titration between strong acid(flask) with strong base(burette) HCI + NaOH → NaCI + H2O

Titration curves Strong Acid with Strong Base

NaOH M = 0.1M V = 0 ml

7

HCI + NaOH → NaCI + H2O

M = 0.1M M = 0.1M

V = 25ml V = 25ml

2.7

11.3

• Rapid jump in pH (2.7 – 11.3) • Rapid change at equivalence point (25ml base) • Equivalence point → amt acid = amt base • End point → indicator change colour • Equvalence point must coincide with end point at 25ml • pH at equivalence point = 7 • Neutral salt, NaCI - neutral

1

HCI M = 0.1M V = 25ml

pH = 1

HCI M = 0.1M V = 1ml left

NaOH M = 0.1M V = 24 ml added

pH = 2.7

NaOH M = 0.1M V = 25ml added

HCI M = 0.1M V = 0ml left

pH = 7

NaOH M = 0.1M V = 26ml

pH = 11.3

NaOH V = 1ml left

Mole ratio – 1: 1 NaOH M = 0.1M V = 25ml

HCI M = 0.1M V = 25ml

Indicator

pKa pH range

Colour Acid

Methyl orange 3.46 3.2- 4.4 RED

Bromophenol Blue 4.10 3.0- 4.6 Yellow

Bromocresol Green 4.90 3.8- 5.4 Yellow

Methyl Red 5.00 4.8- 6.0 Red

Bromothymol Blue 7.30 6.0- 7.6 Yellow

Phenol Red 8.00 6.6- 8.0 Yellow

Phenolphthalein 9.50 8.2- 10.0 Colourless

Indicator

pKa pH range

Colour Base

Methyl orange 3.46 3.2- 4.4 Yellow

Bromophenol Blue 4.10 3.0- 4.6 Blue

Bromocresol Green 4.90 3.8- 5.4 Blue

Methyl Red 5.00 4.8- 6.0 Yellow

Bromothymol Blue 7.30 6.0- 7.6 Blue

Phenol Red 8.00 6.6- 8.0 Red

Phenolphthalein 9.50 8.2- 10.0 Pink

25ml base added: • Equivalence point reach • Indicator change colour

Acidic medium Basic medium

V = 25ml

Titration between strong acid(flask) with strong base(burette) HCI + NaOH → NaCI + H2O

Titration curves Strong Acid with Strong Base

11.3

2.7

NaOH M = 0.1M V = 25ml

HCI M = 0.1M V = 25ml

1

7

V = 25ml

Indicator pKa pH range Colour Change

Acid

Colour Change

Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Bromophenol Blue 4.10 3.0- 4.6 Yellow Blue

Bromocresol Green 4.90 3.8- 5.4 Yellow Blue

Methyl Red 5.00 4.8- 6.0 Red Yellow

Bromothymol Blue 7.30 6.0- 7.6 Yellow Blue

Phenol Red 8.00 6.6- 8.0 Yellow Red

Phenolphthalein 9.50 8.2- 10.0 Colourless Pink Equivalence point occurs when 25ml base added • pH rise sharply (2.7 – 11.3) • Indicator MUST change colour at equivalence point • Indicator with pKa falls in pH range (2.7 – 11.3) suitable • Equivalence Point and End Point coincide when 25ml base added. Indicator change colour at equivalent point (25ml) when pH jumps from 2.7 – 11.3

• pKa indicator within (2.7 – 11.3)

Indicator pKa pH range Acid Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Indicator pKa pH range Acid Base

Phenolphthalein 9.5 8.2 - 10 Colourless PINK

Methyl Orange change colour at 3.2 – 4.4 at equivalence point, 25ml.

Phenolphthalein change colour at 8.2- 10 at equivalence point, 25ml

Methyl Orange can be used as Indicator Phenollphthalein can be used as Indicator

V = 25ml

V = 25ml

11.3 11.3

2.7 2.7

1 1

Titration between strong acid(flask) with strong base(burette) CH3COOH + NaOH → CH3COONa + H2O

Titration curves Weak Acid with Strong Base

NaOH M = 0.1M V = 0 ml

9

CH3COOH + NaOH → CH3COONa + H2O

M = 0.1M M = 0.1M

V = 25ml V = 25ml

6.11

11.3

• Rapid jump in pH (6.11 – 11.3) • Rapid change at equivalence point (25ml base) • Equivalence point → amt acid = amt base • End point → indicator changes colour • Equvalence point must coincide with end point at 25ml • pH at equivalence point = 9 • Basic salt, CH3COONa - basic

2.87

pH = 2.87

NaOH M = 0.1M V = 24 ml added

pH = 6.11

NaOH M = 0.1M V = 25ml added

pH = 9

NaOH M = 0.1M V = 26ml

pH = 11.3

NaOH V = 1ml left

Mole ratio – 1: 1 NaOH M = 0.1M V = 25ml

Indicator

pKa pH range

Colour Acid

Methyl orange 3.46 3.2- 4.4 RED

Bromophenol Blue 4.10 3.0- 4.6 Yellow

Bromocresol Green 4.90 3.8- 5.4 Yellow

Methyl Red 5.00 4.8- 6.0 Red

Bromothymol Blue 7.30 6.0- 7.6 Yellow

Phenol Red 8.00 6.6- 8.0 Yellow

Phenolphthalein 9.50 8.2- 10.0 Colourless

Indicator

pKa pH range

Colour Base

Methyl orange 3.46 3.2- 4.4 Yellow

Bromophenol Blue 4.10 3.0- 4.6 Blue

Bromocresol Green 4.90 3.8- 5.4 Blue

Methyl Red 5.00 4.8- 6.0 Yellow

Bromothymol Blue 7.30 6.0- 7.6 Blue

Phenol Red 8.00 6.6- 8.0 Red

Phenolphthalein 9.50 8.2- 10.0 Pink

25ml base added: • Equivalence point reach • Indicator change colour

Acidic medium Basic medium

CH3COOH M = 0.1M V = 25ml

CH3COOH M = 0.1M V = 1ml

CH3COOH M = 0.1M V = 0ml left

CH3COOH M = 0.1M V = 25ml

V = 25ml

Titration between weak acid (flask) with strong base(burette) CH3COOH + NaOH → CH3COONa + H2O

6.11

11.3 NaOH M = 0.1M V = 25ml

CH3COOH M = 0.1M V = 25ml

2.87

V = 25ml

Titration curve Weak Acid with Strong Base

Equivalence point occurs when 25ml base added • pH rise sharply (6.11 – 11.3) • Indicator MUST change colour at equivalence point • Indicator with pKa falls in pH range (6.11 – 11.3) suitable • Equivalence Point and End Point coincide when 25ml base added.

Indicator pKa pH range Colour Change

Acid

Colour Change

Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Bromophenol Blue 4.10 3.0- 4.6 Yellow Blue

Bromocresol Green 4.90 3.8- 5.4 Yellow Blue

Methyl Red 5.00 4.8- 6.0 Red Yellow

Bromothymol Blue 7.30 6.0- 7.6 Yellow Blue

Phenol Red 8.00 6.6- 8.0 Yellow Red

Phenolphthalein 9.50 8.2- 10.0 Colourless Pink

Indicator change colour at equivalent point (25ml) when pH jumps from 6.11 – 11.3 • pKa indicator within (6.11 – 11.3)

Methyl Orange cannot be used as Indicator

6.11

11.3

2.87

V = 25ml

Methyl Orange change colour at 3.2 – 4.4 before equivalence point, 25ml.

Indicator pKa pH range Acid Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Phenollphthalein can be used as Indicator

11.3

6.11 2.87

V = 25ml

Indicator pKa pH range Acid Base

Phenolphthalein 9.5 8.2 - 10 Colourless PINK

Phenolphthalein change colour at 8.2- 10 at equivalence point, 25ml

Titration curves Strong Acid with Weak Base

NH4OH M = 0.1M V = 0 ml

5.3

HCI + NH4OH → NH4CI + H2O

M = 0.1M M = 0.1M

V = 25ml V = 25ml

2.7

7.8

• Rapid jump in pH (2.7 – 7.8) • Rapid change at equivalence point (25ml base) • Equivalence point → amt acid = amt base • End point → indicator change colour • Equvalence point must coincide with end point at 25ml • pH at equivalence point = 5.3 • Acidic salt, NH4CI – acidic

1

HCI M = 0.1M V = 25ml

pH = 1

HCI M = 0.1M V = 1ml left

NH4OH M = 0.1M V = 24 ml added

pH = 2.7

NH4OH M = 0.1M V = 25ml added

HCI M = 0.1M V = 0ml left

pH = 5.3

NH4OH M = 0.1M V = 26ml

pH = 7.8

NaOH V = 1ml left

Mole ratio – 1: 1

HCI M = 0.1M V = 25ml

Indicator

pKa pH range

Colour Acid

Methyl orange 3.46 3.2- 4.4 RED

Bromophenol Blue 4.10 3.0- 4.6 Yellow

Bromocresol Green 4.90 3.8- 5.4 Yellow

Methyl Red 5.00 4.8- 6.0 Red

Bromothymol Blue 7.30 6.0- 7.6 Yellow

Phenol Red 8.00 6.6- 8.0 Yellow

Phenolphthalein 9.50 8.2- 10.0 Colourless

Indicator

pKa pH range

Colour Base

Methyl orange 3.46 3.2- 4.4 Yellow

Bromophenol Blue 4.10 3.0- 4.6 Blue

Bromocresol Green 4.90 3.8- 5.4 Blue

Methyl Red 5.00 4.8- 6.0 Yellow

Bromothymol Blue 7.30 6.0- 7.6 Blue

Phenol Red 8.00 6.6- 8.0 Red

Phenolphthalein 9.50 8.2- 10.0 Pink

25ml base added: • Equivalence point reach • Indicator change colour

Acidic medium Basic medium

Titration between strong acid(flask) with weak base(burette) HCI + NH4OH → NH4CI + H2O

NH4OH M = 0.1M V = 25ml

V = 25ml

V = 25ml

Equivalence point occurs when 25ml base added • pH rise sharply (2.7 – 7.8) • Indicator MUST change colour at equivalence point • Indicator with pKa falls in pH range (2.7 – 7.8) suitable • Equivalence Point and End Point coincide when 25ml base added

Indicator pKa pH range Colour Change

Acid

Colour Change

Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Bromophenol Blue 4.10 3.0- 4.6 Yellow Blue

Bromocresol Green 4.90 3.8- 5.4 Yellow Blue

Methyl Red 5.00 4.8- 6.0 Red Yellow

Bromothymol Blue 7.30 6.0- 7.6 Yellow Blue

Phenol Red 8.00 6.6- 8.0 Yellow Red

Phenolphthalein 9.50 8.2- 10.0 Colourless Pink

Indicator change colour at equivalent point (25ml ) when pH jumps from (2.7 – 7.8) • pKa of indicator within (2.7 – 7.8)

Titration between strong acid(flask) with weak base(burette) HCI + NH4OH → NH4CI + H2O

Titration curves Strong Acid with Weak Base

NH4OH M = 0.1M V = 25ml

HCI M = 0.1M V = 25ml

2.7

7.8

5.3

1

Indicator pKa pH range Acid Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Indicator pKa pH range Acid Base

Phenolphthalein 9.5 8.2 - 10 Colourless PINK

Phenolphthalein cannot be used as Indicator

7.8

2.7 V = 25ml

1

Phenolphthalein change colour at 8.2- 10 after equivalence point, 25ml .

Methyl Orange can be used as Indicator

7.8

2.7 V = 25ml

Methyl Orange change colour at 3.2 – 4.4 at equivalence point, 25ml.

Titration curves Weak Acid with Weak Base

NH4OH M = 0.1M V = 0 ml

7

CH3COOH + NH4OH → CH3COONH4 + H2O

M = 0.1M M = 0.1M

V = 25ml V = 25ml

6.11

7.8

• No sharp rise in pH at equivalence point (25ml base) • Equivalence point → amt acid = amt base • End point → indicator changes colour • Equvalence point must coincide with end point at 25ml • pH at equivalence point = 7 • Neutral salt, CH3COONH4 – neutral

2.87

pH = 2.87

CH3COOH M = 0.1M V = 1ml left

NH4OH M = 0.1M V = 24 ml added

pH = 6.11

NH4OH M = 0.1M V = 25ml added

CH3COOH M = 0.1M V = 0ml left

pH = 7

NH4OH M = 0.1M V = 26ml

pH = 7.8

NH4OH V = 1ml left

Mole ratio – 1: 1

Indicator

pKa pH range

Colour Acid

Methyl orange 3.46 3.2- 4.4 RED

Bromophenol Blue 4.10 3.0- 4.6 Yellow

Bromocresol Green 4.90 3.8- 5.4 Yellow

Methyl Red 5.00 4.8- 6.0 Red

Bromothymol Blue 7.30 6.0- 7.6 Yellow

Phenol Red 8.00 6.6- 8.0 Yellow

Phenolphthalein 9.50 8.2- 10.0 Colourless

Indicator

pKa pH range

Colour Base

Methyl orange 3.46 3.2- 4.4 Yellow

Bromophenol Blue 4.10 3.0- 4.6 Blue

Bromocresol Green 4.90 3.8- 5.4 Blue

Methyl Red 5.00 4.8- 6.0 Yellow

Bromothymol Blue 7.30 6.0- 7.6 Blue

Phenol Red 8.00 6.6- 8.0 Red

Phenolphthalein 9.50 8.2- 10.0 Pink

25ml base added: • Equivalence point reach • Indicator change colour

Acidic medium Basic medium

NH4OH M = 0.1M V = 25ml

Titration between weak base(burette) with weak acid(flask) CH3COOH + NH4OH → CH3COONH4 + H2O

CH3COOH M = 0.1M V = 25ml

CH3COOH M = 0.1M V = 25ml

V = 25ml

V = 25ml

Equivalence point occurs when 25ml base added • No sharp rise in pH • Indicator MUST change colour at equivalence point • No Indicator suitable

Indicator pKa pH range Colour Change

Acid

Colour Change

Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Bromophenol Blue 4.10 3.0- 4.6 Yellow Blue

Bromocresol Green 4.90 3.8- 5.4 Yellow Blue

Methyl Red 5.00 4.8- 6.0 Red Yellow

Bromothymol Blue 7.30 6.0- 7.6 Yellow Blue

Phenol Red 8.00 6.6- 8.0 Yellow Red

Phenolphthalein 9.50 8.2- 10.0 Colourless Pink

• No indicators are suitable as no sharp rise in pH

NH4OH M = 0.1M V = 25ml

6.11

7.8

7

2.87

Titration curves Weak Acid with Weak Base

Titration between weak base(burette) with weak acid(flask) CH3COOH + NH4OH → CH3COONH4 + H2O

CH3COOH M = 0.1M V = 25ml

Phenolphthalein cannot be used as Indicator

Indicator pKa pH range Acid Base

Phenolphthalein 9.5 8.2 - 10 Colourless PINK

Phenolphthalein change colour at 8.2- 10 after equivalence point, 25ml .

Indicator pKa pH range Acid Base

Methyl orange 3.46 3.2- 4.4 RED Yellow

Methyl Orange change colour at 3.2 – 4.4 before equivalence point, 25ml.

Methyl Orange cannot be used as Indicator

6.11 6.11

7 7

7.8 7.8

V = 25ml

V = 25ml

2.87 2.87

Salt Hydrolysis

Acid + Base → Salt + Water (Neutralization) Salt produced can be • Neutral, pH 7, No hydrolysis • Acidic, pH < 7, Cation hydrolysis • Basic, pH > 7, Anionic hydrolysis Water hydrolysis – chemical reaction involving water in producing H+ and OH- ions

Weak base Strong acid

NH4OH < HCI

↓ Acidic Salt NH4

+ - conjugate acid NH4

+ - Cation hydrolysis NH4

+ + H2O ↔ H3O+ + NH3

Acid (proton donor) pH < 7

Strong base Strong acid NaOH = HCI ↓ Neutral Salt NaCI – dissolves in water NaCI – No water hydrolysis

pH = 7

Strong base Weak acid NaOH > CH3COOH ↓ Basic Salt CH3COO- - conjugate base CH3COO- - Anion hydrolysis CH3COO- + H2O ↔ CH3COOH + OH-

Base (proton acceptor) pH > 7

Acidic Salt Basic Salt Neutral Salt

Strong

Acid

(HCI)

Strong

Base

(NaOH)

NaOH + HCI → NaCI + H2O

Na+ CI-

Strong

Acid

(HCI)

Weak

Base

(NH4OH)

CI- NH4+

NH4OH + HCI → NH4CI + H2O

Strong

Base

(NaOH)

Weak

Acid

(CH3COOH)

Na+ CH3COO-

NaOH + CH3COOH → CH3COONa + H2O

=

Salt Produced Examples Nature of salt

Strong acid + Strong base NaCI, Na2SO4, KNO3 Neutral (No hydrolysis)

Strong Acid + Weak base NH4CI, (NH4)2SO4, NH4NO3 Acidic (Cation Hydrolysis)

Weak Acid + Strong Base CH3COONa, Na2CO3 , Na3PO4 Basic (Anion Hydrolysis)

Weak Acid + Weak Base CH3COONH4, (NH4)3PO4 pH depends on Ka and Kb

Ka > Kb = acidic Kb > Ka = basic

Water hydrolysis

Neutralization bet Strong Acid + Weak Base

Strong

Acid

(HCI)

Weak

Base

(NH4OH)

Acidic Salt

NH4OH + HCI → NH4CI + H2O

NH4+ CI-

Weak base Strong acid

NH4OH < HCI

↓ Acidic Salt NH4

+ - Conjugate acid NH4

+ - Cation hydrolysis NH4

+ + H2O ↔ H3O+ + NH3

Acid (proton donor) pH < 7

Salt Produced Examples Nature of salt

Strong Acid + Weak base

NH4CI, (NH4)2SO4,

NH4NO3

Acidic

Acidic Salt

Salts of Transition Metal ions

Transition metal ions: • SIZE and CHARGE of cation • High charge density – Ni2+, Cu2+,Fe3+, Al3+

• Small size ion – Ni2+, Cu2+,Fe3+, Al3+

http://fineartamerica.com/featured/transition-metal-ion-colours-martyn-f-chillmaid.html

[Fe(H2O)6]3+CI3

Fe

[AI(H2O)6]3+CI3

AI

• 6 H2O attract to Fe3+ ion

• Lone pair on Oxygen act as a ligand • Ligand attract to Fe3+

• Form dative bond

• 6 H2O attract to AI3+ ion

• Lone pair on Oxygen act as a ligand • Ligand attract to AI3+

• Form dative bond

Polarise water/water hydrolysis to produce H+ ions

[Fe(H2O)6]3+ → (H2O)5Fe3+ ← :O―H+ → [(H2O)5FeOH]2+ + H+

|

H Water hydrolysis

Hydrogen ion produced

NH4OH + HCI → NH4CI + H2O

NH4OH + H2SO4 → NH4SO4+ H2O NH4OH + HNO3 → NH4NO3 + H2O

Acidic salt

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Simulation and Animation on Buffer and Titrations

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Click here acidic buffer animation Click here salt hydrolysis animation Click here titration simulation

Click here titration animation Click here titration animation

Click here on universal indicator