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Acids,
Bases, and
Salts1
An acid is a substance that releases hydrogen ions when it dissociates.
Cl-1 Cl-1
H+1
H+1
2
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
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
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
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
Properties of ACIDS:A. They taste sour :(
What can you think of that tastes sour?
7
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
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
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
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
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
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
Both lights are on. Which one is the stronger acid?
14
Examples of Acids: vinegar, fruits, sodas,any food containing fruit juice or vinegar for flavor,and car batteries 15
A strong acid*dissociates completely**forming many hydrogen ions AND, therefore,***forms many hydronium ions.
16
Weak acidsdo not dissociate completely,
they produce few hydrogen ionsAND, therefore,
***form few hydronium ions.
17
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
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
A. taste bitter (cocoa powder, baking soda)B. Feel slippery
PROPERTIES OF BASES:
20
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
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
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
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
Neutral solutions have an equal concentration of H+ ions and OH- ions.
25
Formulas for CommonAcids and Bases
All formulas for acids begin with “H”
Ex. HF, H2CO3 , H3PO4
….etc.26
Formulas forCommon Bases
All formulas for bases end with “OH”
Ex. KOH, Mg(OH)2,,Al(OH)3….etc.
27
From your
previous
experiences, what is
an indicator?
28
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
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
Indicator Results Chart
Indicator
red litmus
blue litmus
phenolphthalein
congo red
Acids BasesNeutrals
31
Indicator Results Chart
Indicator
red litmus
blue litmus
phenolphthalein
congo red
Acids
red
red
clear
blue
Neutrals Bases
32
Indicator Results Chart
Indicator
red litmus
blue litmus
phenolphthalein
congo red
Acids
red
red
clear
blue
Neutrals
red
blue
clear
red
Bases
33
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
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
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
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
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
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
An acid will produce hydrogen more easilythan water, so less acid is needed to produce hydrogen. So, acids have LOW pH values.
40
Bases are assigned high pH values because it requires more of a base to produce hydrogenthan it does water or an acid.
41
42
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
Neutralization - the reaction between an acid and a base, producing water and salt.
44
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
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
Some side effects of acid
rain include dissolving
marble in buildings and
statues, and making soil
and water unsuitable for
many lifeforms.50
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