Unit 8 - Acids, Bases, And Salts Powerpoint (Updated1)

7/27/2019 Unit 8 - Acids, Bases, And Salts Powerpoint (Updated1)

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UNIT 8:

ACIDS, BASES, AND SALTS

TOPIC 1:

PROPERTIES OF

ARRHENIUS ACIDS AND

BASES


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I. WHAT IS AN ACID (ARRHENIUS

ACID?

To be an acid, it must be dissolved in __________ When acids are dissolved in ______________ ,

they ______________ and form

______________________

IMPORTANT: ACIDS ARE SUBSTANES THAT

CONTAIN

See Table ___ in Reference Tables for

________________

H2O

H2OBREAK APART FREELY MOVING IONS

H+ IONS THAT IONIZE WHEN DISSOLVED IN WA

K COMMON ACIDS


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I. WHAT IS AN ACID (ARRHENIUS

ACID?

Example: When an acid is dissolved in water, theH+ leaves the acid and bonds to the water

molecule to form a ________________________

HCl (g) + H2O (l) H3O+ (aq) + Cl - (aq)

The acid HCl contains 1 H+ which combines with 1

H2O to form 1 H3O+

HYDRONIUM ION (H3O+)

Dissociation of acids in water animation
http://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/ct2.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/ct2.htm


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II. PROPERTIES OF ACIDS

A) Acids eat away (oxidize) active metals to produce_____________________

Example: 2 Li + 2 HCl ________________(__________________________________________)

B) Acids have a __________________(we willdiscuss this more later on)

HYDROGEN GAS

2 LiCl + H2

METAL HAS TO BE ABOVE HYDROGEN

ON TABLE J

pH LESSTHAN 7


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II. PROPERTIES OF ACIDSC) Acids are ________________, meaning the

_______________________________________

D)Acids taste ________(like _________, but DO NOT

TASTE unknown substances)

ELECTROLYTESCONDUCT ELECTRICITY WHEN DISSOLVED IN

WATER

SOUR LEMONS


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III. WEAK VS. STRONG ACIDS Acids always produce H

3O+ (hydronium) ions when

dissolved in water. The more H+ that dissociate when

in water, the stronger the acid will be.

Examples of Strong Acids____________________

Example of Weak Acid ______________

HCl, HNO3, HBr, HI

CH3CH2COOH

(HC2

H5

O2

)

(org anic acids )

WEAK VS. STRONG ACID

ANIMATION
http://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons3.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons3.htmhttp://www.mhhe.com/physsci/chemistry/chang7/esp/folder_structure/ac/m2/s1/acm2s1_1.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons3.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons3.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons3.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons3.htm


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.BASE) IMPORTANT: BASES ARE SUBSTANES THAT

CONTAIN

See Table _________ in Reference Tables for

____________________

Example: When a base is dissolved in water, the

OH - 1 leaves the base

NaOH (s)______________________

OH- (Hydroxide) ions dissolved in aqueous

solution.

L

COMMON BASES

Na + 1 (aq) + OH - 1 (aq)


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V. PROPERTIES OF BASES A) Bases have a _______________ (we will discuss

this more later on)

B) Bases are _______________, meaning

_________________________________

C)Bases taste ______________ (like _________)

D)Bases hydrolyze fats (turns them into soap,also called saponification)

The manufacture of soap involves heating up animal fat or vegetable oil,

(for example, glyceryl stearate) dissolving it in alcohol and adding NaOH

or KOH to it slowly. This forms a soap (for example, sodium stearate),

pH above 7

ELECTROLYTESTHEY CONDUCT ELECTRICITY WHEN

DISSOLVED IN WATER

BITTER SOAP/

MEDICINE


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. .BASES

Like acids, the more ions that dissociate in water, the

stronger the base is. Bases formed with group 1 and

2 metals are typically stronger.

Examples of Strong Bases __________________

Example of Weak Bases ___________________

LiOH, NaOH, Mg(OH)2

Al(OH)3, NH4OH


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UNDERSTANDING

1) Identify the following as acids or bases

2) Identify it as a strong or weak acid/base

1) NaOH __________ 4) H2SO4

___________

2) H3BO3 __________ 5) HC2H3O2

___________

3) KOH __________ 6) Ca(OH)2

_________

base

acid

base

acid

acid

base

(strong)

(strong)

(strong)

(strong)

(weak)

(strong)


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.BASES

Naming Binary Acids (metal with nonmetal):

- Name the hydrogen in the acid hydro-

- Name the anion and change ending of the name to ic

acid

Examples:

1. HCl (aq) - _ ____________________________

2. HI (aq) - _____________________________

3. HBr(aq) - ____________________________

4. H2S(aq) - _____________________________

Hydrochloric acid

Hydroiodic acid

Hydrobromic acid

Hydrosulfuric acid


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.BASES

Naming Ternary Acids (metal with PAIs)

Go to Table ______ and name the PAI (polyatomic

ion)

DO NOT use the prefix hydro

If the PAI ends in - ate, it changes toic acid

If the PAI ends in i te, it changes to ous acid

Examples:1) H2CO3 (aq) - _ ____________________________

2) H3PO4 (aq) - _____________________________

3) H2SO4 (aq) - _____________________________

E

Carbonic acid

Phosphoric acid

Sulfuric acid

Sulfurous acid


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.BASES

Naming Bases:

- Bases are all ____________________, therefore, they

are named just like ________________

Name 1st element

Use roman numeral if the metal has more than one

charge listed

2nd half of the name will typically be

_______________

Examples:

1. NaOH (aq) - ____________________

IONIC COMPOUNDS

IONIC COMPOUNDS

Sodium hydroxide

HYDROXIDE


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.BASES

Naming Bases (continued):

2. Ca(OH)2 (aq) - _____________________________

3. Fe(OH)3 (aq) - _____________________________

4. Co(OH)2 (aq) - _____________________________

Calcium hydroxide

Iron (III) hydroxide

Cobalt (II) hydroxide

VIII HOW TO KNOW IF A


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VIII. HOW TO KNOW IF A

SOLUTION IS ACIDIC OR BASIC

Indicator

Acid-Base Indicators (Found on Table ___________)

Acid-Base Indicators and narrowing down pH usingmultiple indicators (mixture of indicators gives great

range of colors, pH paper)

Remember: An acid has a pH _________________

and a base has a pH

_________________

a substance that changes color if an acid o

M

less than 7

above 7



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Tips Using Table M:

If the indicator changes TOthe listed color, pH is

___________ the pH range.

If the indicator does NOTchange, pH is __________ the pH

range.

The pH range does NOT indicate that the solution has pH

within that range

above

below


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TIPS ON USING TABLE M Tip 1- Notice "Common Acid

Base Indicators," acid is on the

left and base is on the right.

Low pH numbers are on the left

and high pH numbers are onthe right. They match up.

Tip 2 - Look at Methyl Orange,

red is on the left, 3.2 is on the

left. To the left (or below) a pHof 3.2 the color is red.

To the right (above) a pH of 4.4

the color is yellow.

-



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Example: A solution has a pH of 5.5. What colorchanges will happen to following indicators.

1) Methyl orange __________ 3) Bromscresolgreen____________

2) Bromthylmol blue ________ 4) Thymol blue______________

yellow

yellow

blue

yellow



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Example: A solution yields the following results when

tested with various indicators:

Methyl Orange = yellow

Phenolphthalein = clear

Bromcresol Green = blue

Thymol Blue = yellow

- Can the pH be:a) 2.8 b) 6.5 c) 8.5 d) 4.8

pH above4.4

XXXX

pH below8.0

XXX

X

pH above5.4

XXXX

pHbelow 8


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UNIT 8:ACIDS, BASES, AND SALTS

TOPIC 2:

ACID AND BASE

NEUTRALIZATION


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THINK ABOUT THIS If you add a strong acid to a base, what would

happen to the pH of the mixed solution?


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.NEUTRALIZATION

Neutralization: When an acid and base are mixed,

the ____________________ and

the ______________________ combine to form

_______________. The anion of the acid and the

cation of the base come together to form a_________________.

Neutralization of Acid and Base Video Clip

Double Replacement AnimationRainbow Connection Demo (Titration with pH indicators)

Salt

H+ of the

acid

OH --- of the

baseWater (H2O)

salt

An ionic compound (metal with

nonmetal/PAI) that can be formed by acid-

base neutralization
http://www.youtube.com/watch?v=8IRI5gPR5EY&feature=player_embedded&safety_mode=true&persist_safety_mode=1&safe=activehttp://www.kentchemistry.com/links/AcidsBases/flash/neutralization.swfhttp://www.youtube.com/watch?v=lCrMB8341rU&safety_mode=true&persist_safety_mode=1&safe=activehttp://www.youtube.com/watch?v=lCrMB8341rU&safety_mode=true&persist_safety_mode=1&safe=activehttp://www.youtube.com/watch?v=lCrMB8341rU&safety_mode=true&persist_safety_mode=1&safe=activehttp://www.youtube.com/watch?v=lCrMB8341rU&safety_mode=true&persist_safety_mode=1&safe=activehttp://www.kentchemistry.com/links/AcidsBases/flash/neutralization.swfhttp://www.youtube.com/watch?v=8IRI5gPR5EY&feature=player_embedded&safety_mode=true&persist_safety_mode=1&safe=active


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.NEUTRALIZATION

Examples:

1) HCl (aq) + NaOH (aq)

_____ _____ ______ ___________

2) H2SO4(aq) + 2 __________ K2SO4 (aq) + 2

_________

_______ _______ ___________

___________

3) 2 HNO3(aq) + __________ Ca(NO3)2 (aq) + 2

__________

acid bas

e

HOH

(l) +

NaCl(a

q)water salt

acid bas

e

salt wat

er

HOH(

l)KOH

(aq)

acid base salt water

HOH (l)Ca(OH)2(aq)

DOUBLE REPLACEMENT

REACTIONS!!!


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.NEUTRALIZATION

Example: Write the equation for the neutralizationreaction between dilute nitric acid (HNO3) and

potassium hydroxide (KOH). (DONT FORGET TO

BALANCE)___ HNO3( aq) + ___ KOH (aq) ___ H(OH)(l) + ___K(NO3)(aq)

1 1 1 1

water Potassium nitrate


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.NEUTRALIZATION

Example: Write the equation for the neutralizationreaction between dilute Mg(OH)2 and HCl. (DONT

FORGET TO BALANCE)___ Mg(OH)2 ( aq) + ___ HCl (aq) ___ H(OH)(l) + ___MgCl2(aq)

2 21 1


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WORKSHEET

Complete problems 1, 3, and 5 with your assignedpartner.

Write the general chemical equation for a

neutralization reaction:

Example: lithium hydroxide is mixed with carbonic

acid.


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1) Ba(OH)2(aq) + 2HCl(aq) BaCl2 (aq) + 2H2O(l) bariumbarium hydroxide + hydrochloric acid barium chloride + water

WORKSHEET (ANSWERS)

2) 2Al(OH)3(aq) + 3H2SO4(aq) Al2(SO4)3(aq) + 6H2O(l)

aluminum hydroxide + sulfuric acid aluminum sulfate + water

3) 3Fe(OH)2(aq) + 2H

3PO

4(aq) Fe3(PO4)2(aq) + 6H2O(l)

iron (II) hydroxide + phosphoric acid iron (II) phosphate + water


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5) 2NH4OH(aq) + H2S(aq) (NH4)2S(aq) + 2H2O(l)

ammonium hydroxide+ hydrosulfuric acid ammonium sulfide

+ water

WORKSHEET (ANSWERS)

4) Ca(OH)2(aq) + 2HNO3(aq) Ca(NO3)2(aq) + 2H2O(l)calcium hydroxide + nitric acid calcium nitrate + water

6) KOH(aq) + HClO2(aq) KClO2(aq) + H2O(l)

potassium hydroxide + chlorous acid potassium chlorite+ water


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X. TITRATION (VIDEO DEMO)

Definition: process of adding a known amount ofsolution of known concentration to determine the

concentration of another solution

moles of H+1 (aq) = moles of OH-1 (aq)

Molarity of Acid * Volume of Acid = Molarity of base *

Volume of Base

Titration Equation (see Table T):

One mole of H+

neutralizes one moleof OH --

MA(VA) = MB(VB)O

R(#H+)(MA)(VA) = (#OH---)(MB)(VB)

Titration Animati

Titration Animati
http://www.youtube.com/watch?v=g8jdCWC10vQhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons9.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons9.htmhttp://chem-ilp.net/labTechniques/TitrationAnimation.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons9.htmhttp://www.chembio.uoguelph.ca/educmat/chm19104/chemtoons/chemtoons9.htmhttp://chem-ilp.net/labTechniques/TitrationAnimation.htmhttp://www.youtube.com/watch?v=g8jdCWC10vQ


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X. TITRATION

Example: What is the concentration of hydrochloricacid solution if 50.0 mL of a 0.250 M KOH are

needed to neutralize 20.0 mL of the HCL solution of

unknown concentration?#H+= 1

#OH--- = 1

MA = ?

VA = 20.0 mL

VB = 50.0 mL

MB = 0.250 M

(#H+)(MA)(VA) = (#OH---)(MB)(VB)

MA = 0.625 M


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X. TITRATION

Example: What is the concentration for sulfuric acidsolution if 50 mL of a 0.25 M KOH are needed to

neutralize 20 mL of the sulfuric solution of unknown

concentration?#H+= 2

#OH--- = 1

MA = ?

VA = 20.0 mL

VB = 50.0 mL

MB = 0.250 M

(#H+)(MA)(VA) = (#OH---)(MB)(VB)

MA = 0.313 M

H2SO4


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X. TITRATION

Example: How many mL of 2.0 M H2SO4 arerequired to neutralize 30.0 mL of 1.0 M NaOH?

#H+= 2

#OH--- = 1

MA = 2.0 M

VA = ?

VB = 30.0 mL

MB = 1.0 M

(#H+)(MA)(VA) = (#OH---)(MB)(VB)

VA = 7.5 mL


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X. TITRATION

Example: How many mL of 0.10 M Ca(OH)2 arerequired to neutralize 25.0 mL of 0.50 M HNO3?

#H+= 1

#OH--- = 2

MA = 0.50 M

VA = 25.0 mL

VB = ??

MB = 0.10 M

(#H+)(MA)(VA) = (#OH---)(MB)(VB)

VB = 62.5 mL


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ACTIVITY

With a partner and on a separate piece of paperanswer question 2-12 (evens only) on pages 16-17

in the Unit 8 Work Packet.

- Be sure to show ALL your work

- I will collect one persons paper from each group

to grade.


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UNIT 8:ACIDS, BASES, AND SALTS

TOPIC 3:

PH SCALE

XI THE POWER OF HYDRONIUM


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XI. THE POWER OF HYDRONIUM

(WHAT PH REALLY MEANS)

The pH scale is easiest method to use for comparingthe strengths of acids and bases. We test our fish

tanks (fish pee out ammonia, which is a base, and

brings the pH up), our lawns (acid rain brings the pH

of the soil down) and even food is pH tested as it isbeing made to make sure that it falls within the right

range. You wouldnt want your super sour candy to

have too little bite, would you? So just what is this pH,

what does it mean, and how is it measured?

Water breaks up very slightly to form hydrogen ions

and hydroxide ions:

H2O H +1 + OH 1

7



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.(WHAT PH REALLY MEANS)

A pH of 0-7 is __________ When the

concentration of H+ is...

A pH of 7 is ____________ 10-1 M, pH = ____,

10 -2, pH =___

acidic

neutral

basic

1 2

3



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The pH scale is logarithmic. Each change of a single

pH unit signifies a tenfold change in the concentration

of the hydrogen ion. Therefore, the[H+] is ten times

greater in a solution of pH of 5 as in a solution of pH of

6. Examples:

A) A solution with pH of 3 is 10 times more acidic than

solution with a pH of ____

B) A solution with pH of 3 is ___________ times more

acidic than solution with a pH of 6.

4 (for every power of 10, pH goes UP

1)1,000

6



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The pH scale is logarithmic. Each change of a single

pH unit signifies a tenfold change in the concentration

of the hydrogen ion. Therefore, the[H+] is ten times

greater in a solution of pH of 5 as in a solution of pH of

6. Examples (continued):

D) A sample of base has pH of 9. What would the pH of

a base 1,000 more basic be?

E) A sample of acid has a pH of 3. What would be the

12 (for every power of 10, the pH goes

UP 1 becomes more basic)

1 (for every power of 10, the pH goes

DOWN 1 becomes more acidic)



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UNIT 8:

ACIDS, BASES, AND SALTS

TOPIC 4:

ALTERNATIVE THEORY OF

ARRHENIUS ACIDS AND

BASES

AND BASES (BRONSTED-LOWRY


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ACIDS AND BASES)A. Review Arrhenius Acids and Bases

Acids: ___________ ions are the only____________

ions in water

Bases: ___________ ions are the only ___________

ions in water

B. Bronsted-Lowry (Alternate Theory)Acids and

Bases

Acids: are proton

___________________________________

Bases: are proton

H + (aq) POSITIV

EOH ---

(aq)

NEGATIV

E

DONORS, GIVE AWAY H+ (aq) to

another substanceACCEPTORS, RECEIVE H+ (aq) fromanother substance



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ACIDS AND BASES)

C. Conjugate Acid-Base Pairs

Consists of two substances related by the loss or

gain of a single hydrogen ion

The ionization of HCl: HCl (aq) H+1 (aq) + Cl-1(aq)

Animation

Example:

HCl (aq) + HOH (l) Cl -1 (aq) + H3O+1 (aq)

One acid and one base per sideOne that gains H+ is the conjugate

acid

One that loses H+ is the conjugate

Aci

d

Base

Conjugat

e base

Conjugat

e acid

http://chemmovies.unl.edu/ChemAnime/HYCLWD/HYCLWD.htmlhttp://chemmovies.unl.edu/ChemAnime/HYCLWD/HYCLWD.htmlhttp://chemmovies.unl.edu/ChemAnime/HYCLWD/HYCLWD.html


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ACIDS AND BASES)

Example:

NH3 (aq) + HOH (l) NH4+1 (aq) + OH-1 (aq)

HOH (l) + HOH (l) H3O+ (aq) + OH-1 (aq)

HC2H3O2 (aq)+ H2O (l) H3O + (aq) + C2H3O2 (aq)

Bas

e

Acid Conjugate

acid

Conjugat

e base

Bas

e

Acid Conjugate

acid

Conjugat

e base

Aci

d

Base Conjugate

acid

Conjugat

e base



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ACIDS AND BASES)

Examples: Based on the acid-base theory (Bronsted-LowryAcid and Base), identify the acid and base for the following:

Remember:

B/L acid: LOSE H+ in the reaction B/L base: GAINH+ in the reaction

NH3 + H2SO4 NH4+ + HSO4

HBr + NH2- NH3 + Br

-

NH3 + HCl NH4+ + Cl -

B A CA

C

B

A B CA

C

B

Unit 8 - Acids, Bases, And Salts Powerpoint (Updated1)

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