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Acids, Bases, and Salts 1

Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

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Page 1: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Acids,

Bases, and

Salts1

Page 2: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

An acid is a substance that releases hydrogen ions when it dissociates.

Cl-1 Cl-1

H+1

H+1

2

Page 3: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

An acid is a substance that releases hydrogen ions when it dissociates in water.

Cl-1 Cl-1

H+1

H+1

”dissociate” -To split up or decompose

3

Page 4: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

The solution that forms is called hydrochloric acid.This solution also contains water. The hydrogen ions produced by an acid are attracted to water molecules.

HCl ---------> H+ + Cl-

4

Page 5: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Hydronium ions, H3O+ ions, are

formed when the hydrogen ion binds with the water.

O-2

H+1 H+1 H+1

H+1

H+1

O-2

H+1

H2O + H+ ---> H3O+

5

Page 6: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Acids are also defined as

substances that produce

hydronium ions.

O-2

H+1 H+1 H+1

H+1

H+1

O-2

H+1

6

Page 7: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Properties of ACIDS:A. They taste sour :(

What can you think of that tastes sour?

7

Page 8: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

PROPERTIES OF ACIDS:A. They taste sour (lemons,

jawbreakers, vinegar, some sodas)because of acids like:- citric acid…. in fruits- acetic acid… is vinegar!- ascorbic acid (Vitamin C)….

added for that sour taste

8

Page 9: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Properties of Acids:A. They taste sour ( lemons, jawbreakers, vinegar, some sodas).

B. They react with some metals to produce hydrogen gas.2HCl + Mg ----->MgCl2 + H2

9

Page 10: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

PROPERTIES OF ACIDSA. They taste sour, ( lemons, jawbreakers, vinegar, some sodas)

B. they react with some metals to produce hydrogen gasHCl + Mg -----> MgCl2 + H2

Hydrogen is diatomic!!!

Match up the ionic charges to make proper formulas!

10

Page 11: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

PROPERTIES OF ACIDSA. They taste sour, ( lemons, jawbreakers, vinegar, some sodas)

B. they react with some metals to produce hydrogen2HCl + Mg -----> MgCl2 + H2

HF + Cu ---->

IF this metal is higher on the activity series than H, it will react with the acid to release hydrogen gas!

11

Page 12: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Obj #2 Properties of Acids :A. They taste sour, ( lemons, jawbreakers, vinegar, some sodas)

B. they react with some metals to produce hydrogen2HCl + Mg -----> MgCl2 + H2

HF + Cu ----> NO REACTION

Copper is lower on the activity series than hydrogen, so it will not react.

12

Page 13: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

PROPERTIES OF ACIDSA. They taste sour, ( lemons, jawbreakers, vinegar, some sodas)

B. they react with some metals to

produce hydrogen

C. they conduct electricity.Have you ever seen a potato clock or a clock with wires going from a Pepsi into the clock? The wires aren’t actually touching. The items usually “wired up” contain enough natural acids to allow electricity to flow.

13

Page 14: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Both lights are on. Which one is the stronger acid?

14

Page 15: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Examples of Acids: vinegar, fruits, sodas,any food containing fruit juice or vinegar for flavor,and car batteries 15

Page 16: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

A strong acid*dissociates completely**forming many hydrogen ions AND, therefore,***forms many hydronium ions.

16

Page 17: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Weak acidsdo not dissociate completely,

they produce few hydrogen ionsAND, therefore,

***form few hydronium ions.

17

Page 18: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

A base is a substance that forms hydroxide ions, OH- .A hydroxide ion contains one

oxygen atom and one hydrogen atom.

Na+ Na+

O-

O-

H+

H+

18

Page 19: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

A. taste bitter (cocoa powder, baking soda)Have you ever tasted raw cocoa powder,... or accidentally got soap in your mouth when you sneezed in the shower?

PROPERTIES OF BASES:

19

Page 20: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

A. taste bitter (cocoa powder, baking soda)B. Feel slippery

PROPERTIES OF BASES:

20

Page 21: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Properties of Bases:A. taste bitter (cocoa powder, baking soda)

B. feel slippery (soap, clothing detergent or bleach on your hands)

One of the key things that makes soaps work is that they are very slippery and you don’t stop the friction between your hands under water until that slipperiness is gone! The dirt slips off….

21

Page 22: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Properties of Bases:A. taste bitter (cocoa powder, baking soda)

B. feel slippery (soap, detergent, bleach)C. dissolve fats and oils (soap, detergent, bleach)

D.conduct electricity(All faucet water has metals that conduct electricity anyway. Now the soap does too? That’s one more reason why people shouldn’t take a bath with a radio plugged in close by!)

22

Page 23: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Properties of Bases:A. taste bitter (cocoa powder, baking soda)

B. feel slippery (soap, detergent, bleach)C. dissolve fats and oils (soap, detergent, bleach)

D.conduct electricityExamples of Bases: Soap, bleach, detergents, ammonia,windex, and most

cleaners

23

Page 24: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Strong bases dissociate completely and produce manyOH- ions in water solution.

Weak bases do not dissociate completely and produce few hydroxide ions in water solution.

24

Page 25: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Neutral solutions have an equal concentration of H+ ions and OH- ions.

25

Page 26: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Formulas for CommonAcids and Bases

All formulas for acids begin with “H”

Ex. HF, H2CO3 , H3PO4

….etc.26

Page 27: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Formulas forCommon Bases

All formulas for bases end with “OH”

Ex. KOH, Mg(OH)2,,Al(OH)3….etc.

27

Page 28: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

From your

previous

experiences, what is

an indicator?

28

Page 29: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Indicators of how acidic or basic something is

include: purple grapes, purple cabbage, red

onions, and hydrangea flowers.

In nature, certain trees, fish or birds dying

indicate the lack of health in an environment.

29

Page 30: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

An indicator is a compound that changes color as the concentration of H+ or OH- ions changes. These compounds are sensitive to small changes in ionconcentrations.

30

Page 31: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Indicator Results Chart

Indicator

red litmus

blue litmus

phenolphthalein

congo red

Acids BasesNeutrals

31

Page 32: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Indicator Results Chart

Indicator

red litmus

blue litmus

phenolphthalein

congo red

Acids

red

red

clear

blue

Neutrals Bases

32

Page 33: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Indicator Results Chart

Indicator

red litmus

blue litmus

phenolphthalein

congo red

Acids

red

red

clear

blue

Neutrals

red

blue

clear

red

Bases

33

Page 34: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Indicator Results ChartIndicator

red litmus

blue litmus

phenolphthalein

congo red

Acids

red

red

clear

blue

Neutrals

red

blue

clear

red

Bases

blue

blue

pink

red

34

Page 35: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Another way to find the pH of a

solution is to use pH paper (strips of paper are coated with a mixture of various indicators).This paper will indicate pH values that are accurateto 0.1 on the pH

scale.

35

Page 36: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

The pH scale:a. gives a measure of the H+ ion

concentration of a solution b. describes the acidity of a solution and

can be expressed using a scale of numbers ranging from 0 to 14,

0 1 2 3 4 5 6

7

8 9 10 11 12 13 1436

Page 37: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

The pH scale;a. gives a measure of the H+ ion

concentration of a solution . b. describes the acidity of a solution can

be expressed using a scale of numbers c. ranges from 0 to 14,

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

ACIDSproduce the most H+ ions 37

Page 38: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

The pH scale:a. gives a measure of the H+ ion

concentration of a solution . b. describes the acidity of a solution can

be expressed using a scale of numbers c. ranges from 0 to 14,

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14neutral

Make equal amounts of H+

and OH- 38

Page 39: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

The pH scale:a. gives a measure of the H+ ion

concentration of a solution . b. describes the acidity of a solution can

be expressed using a scale of numbers c. ranges from 0 to 14,

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

BASES produce the least H+

neutral

39

Page 40: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

An acid will produce hydrogen more easilythan water, so less acid is needed to produce hydrogen. So, acids have LOW pH values.

40

Page 41: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Bases are assigned high pH values because it requires more of a base to produce hydrogenthan it does water or an acid.

41

Page 42: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

42

Page 43: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

An acid will produce hydrogen more easily than water,

so less acid is needed to produce hydrogen. Bases are assigned high pH values because it requires more of a base to produce hydrogen than it does water or an acid.

Examples:pH 1 = gastric acid pH 8 = raw eggpH 2-3 = lemon juice, vinegar pH 8-9 = baking sodapH 4 = soda water, tomato juice pH 10 = bar soappH 5 = black coffee, banana pH 11-12 = ammoniapH 7 = pure water pH 14 = lye, oven

cleaner

43

Page 44: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Neutralization - the reaction between an acid and a base, producing water and salt.

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Page 45: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Acid rain is any rain that has a pH below 5.6. (Normal rainfall has a pH of approximately 5.6.A rainfall with a pH of 4.6 is actually 10 times more acidic thannormal.)

48

Page 46: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Acid rain is caused by sulfur oxides and nitrogen oxides reacting with the atmosphere to form acids.

NO2 + H2O ---> HNO3

SO2 + H2O ---> H2SO3

SO3 + H2O ---> H2SO4

CO2 + H2O ---> H2CO349

Page 47: Acids, Bases, and Salts - Eagle chemistry · 2018. 9. 10. · jawbreakers, vinegar, some sodas) because of acids like: - citric acid…. in fruits - acetic acid… is vinegar! - ascorbic

Some side effects of acid

rain include dissolving

marble in buildings and

statues, and making soil

and water unsuitable for

many lifeforms.50