water solutions of acids universal indicator is yellow turn phenolphthalein colorless turn litmus...

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Water Solutions of Acids

• Universal Indicator is yellow

• Turn phenolphthalein colorless

• Turn litmus paper red

• React with metals to give off hydrogen gas

• Taste Sour

Water Solutions of Bases

• Taste bitter and feel slippery

• Do not react with metals

• Conduct electricity

• Turn litmus paper blue

• Turn phenolphthalein pink

• Universal Indicator is blue

Svante Arrhenius

Svante Arrhenius:

Acids form hydronium ions in water while bases form hydroxide ions.

Hydronium ions: [H3O+] (H+ combined with H2O)

Hydroxide ions: [OH]

Hydronium Ion

WaterMolecule

O

H

H

Hydronium Ion

O

H

H

H

+

+

+

+

H3O

WaterMolecules

HydroniumIon

Water polarity

Water Molecule

Oxygen

Hydrogen

Hydrogen

+

+

WaterWater Molecule

OxygenAtom

Hydrogen AtomHydrogen Atom

+ +

+

+

H

H

O

Hydrogen Bond

HydrogenBonding

Hydrogen BondingHydrogen Bonding

H2O

WaterMolecules

HydroniumIon

+ +

+

++

NO3

Nitric Acid in waterHNO3 + H2O NO3

+ H3O+

H3O+

Svante Arrhenius:

Acids form hydronium ions in water while bases form

Hydronium ions: [H3O+] (H+ combined with H2O)

Hydroxide ions: [OH]

hydroxide ions

HydroxideIon

O H +

OH

OH

Sodium Hydroxide in water

NaOH + H2O Na+ + OH + H2O

Na+

HydratedAl+3

Al+3

H2O

H2O

H2O

H2O

H2O

H2O

StrongAcid

WeakAcid

Neutral Strong Base

WeakBase

O

O

O

O

S

HH

O

O

O

N

H

O

O

O

N

NO3

Nitrate Ion

Cu + 4 HNO3 Cu(NO3)2 + 2 NO2 + 2 H2O

The brown gas is NO2

The green material isCu(NO3)2

Nitric Acid is an oxidizing acid

Acid and Base Strength 

Acid strength depends on the number of hydronium ions formed per mole of acid.

HNO3 is a strong acid and HF is a weak acid. The ionization of hydrofluoric is

more reversible the HNO3 ionization.

HF + H2O F + H3O +

HNO3 + H2O NO3 + H3O +

reversible

HydroniumIon

NitrateIon

100 % Ionized

Strong Acid

HNO3

FluorideIon

HF

HydroniumIon

Weak Acid

HFReversible

Cl

H

100 % Ionized

Strong Acid

100 % Ionized

Strong Acid

O

O

C

H

Bond

O

O

C

C

H

H HH

CH3COOH

Acid and Base Strength 

Acid strength depends on the number of hydronium ions formed per mole of acid.

HCl is a strong acid and acetic acid is a weak acid. The ionization of acetic acid is

more reversible the HCl ionization.

 CH3COOH + H2O CH3COO + H3O

+

HCl + H2O Cl + H3O+

weak acidstrong acid

IodideIon

HydroniumIon

100 % ionization

Strong Acid

HI

100 % ionization

Strong Base

Johannes Brønsted

Johannes Brønsted:

Definition based on what happens during an acid base reaction

and is not limited to aqueous solutions.

Brønsted Base

A substance that accepts an H+ ion (proton) from another substance

Brønsted Acid

A substance that donates an H+ ion (proton) to another substance

Acid – A substance that produces hydrogen ions in water solution.

HCl H+ + Cl

Acids and Bases

Base – A substance that produces hydroxide ions in water solution.

 NaOH Na+ + OH

An acid is a proton donor.

A base is a proton acceptor.

Brønsted states

Brønsted states

Conjugate Acid – A particle obtained after a base has gained a proton.

Conjugate Base – A particle remaining after an acid has donated a proton.

Conjugate Acid and Conjugate Base

Brønsted Used The Acid-Base Reaction

To Define The

NH3 + HCl NH4+ + Cl

Conjugate Acid and Conjugate Base

BaseCan Accept a

Proton

AcidCan Donate a

Proton

Conjugate AcidHas Accepted

A Proton

Conjugate BaseHas Donated

A Proton

The ProtonIs Gone !

Conjugate Acid and Conjugate Base

Acid Conjugate Acid

BaseConjugate Base

HNO3 + H2O H3O+ + NO3

HCN + SO42 HSO4

+ CN

Conjugate Acid and Conjugate Base

Acid Conjugate Acid

BaseConjugate Base

Base

Acid

ConjugateAcid

ConjugateBase