Day 1Acid-Base

Review of naming acids

Determine Name: H2SO3

H2SO4

H2S

HClO3

HCl

HClO2

Determine Name: H2SO3

H2SO4

H2S

HClO3

HCl

HClO2

Determine Formula

Hydrofluoric acid

Carbonic acid

Nitrous acid

Hydroselenic acid

Determine Formula

Hydrofluoric acid HFCarbonic acid

Nitrous acid

Hydroselenic acid

Characteristics of Acids & Bases

Acids are Characterized by:

OSour tasteO color of indicator ORelease of H2 gasOReacts with bases salt( ionic

compound) & H2O

Bases are Characterized by:

OBitter tasteOFeels slipperyO color of indicator OReacts with acid salt( ionic

compound) & H2OOConducts electric current ( its

an ionic compound)

What does ionization mean?

Ionization OAdding or removing

electrons (e-)OMaking a cation or anion

Strong AcidsOIonizes completely = breaks

up completely OConducts electric current

(remember electrolyte demo & PhET)

Strong AcidsExamples:

OHydrochloric Acid (HCl)

OSulfuric Acid (H2SO4) ONitric Acid (HNO3)

Strong BaseOIonizes completely = breaks up

completely OExamples: group 1 hydroxides –

sodium hydroxide, potassium hydroxide, etc.

Neutralization Reaction HCl + NaOH NaCl + HOHStrong + Strong Salt + Water Acid BaseHNO3 + KOH KNO3 + HOH

Neutralization ReactionIs a double replacement rxn b/w …

strong acid + strong base a salt (ionic compound) + water

pH ScaleDetermining strength of an Acid

or Base

pH scale 0-14 Oneutral pH = 7.0

Oacidic pH <7.0

Obasic pH > 7.0

pH Scale

Calculating pH & [H+]

pH = -log[H+]Inverse of log10 is 10^( )

[H+] = 10^(-pH)

Calculating pOH & [OH-]

pH = -log[OH-]Inverse of log10 is 10^( )

[OH-] = 10^(-pOH)

Relationship between pH & pOH

pH + pOH = 14

Now you try…

Answer

Try on your own…

Try on your own…

Practice

Now you try

Answer

Try on your own..

Answers

Other methods of determining pH

If molarity is not known, pH can be determined by…

OAcid-Base Indicators

OpH meterOTitration

Indicator SolutionsOChange color

depending on pH of test solution

Indicators

Indicators

Indicators

Problems with indicator solutions:

OIf you have a colored solution

OApprox pH value not exact

OTemperature affects color

pH meter

pH meter Oconsists of a measuring probe Oelectronic meter: measures &

displays the pH readingOhave to calibrate probe

TitrationOUse Buret, Erlenmeyer flask,

indicatorOUse M1V1 = M2V2 to determine

molarity of unknown

Titration

Titration

Answer the following questions while watching the video clips: 1. Where do you read/How do you read a

burette? 2. What hand do you use to swirl the

Erlenmeyer flask? 3. What hand do use to adjust the burette? 4. When do you know you are getting close to

the endpoint? 5. How is the standard solution added as you

get close to the endpoint? 6. When do you know you have achieved the

endpoint?

OTitration Video Clip #1 (3:15)

OTitration Video Clip # 2 ( 6:07)

Now, do the titration pre-lab