Acids and Bases/The pH Scale and Indicators

Question 1

Acid Definition

Answer 1

A compound that produces hydrogen ions, H+ (aq), when dissolved in water.

Question 2

True or False: Many acids are corrosive, and will react with metals.

Answer 2

True

Question 3

Why do aqueous solutions of acids conduct electric current?

Answer 3

Because of the ions present in the solution.

Question 4

What is the process called when an acid dissolves in water, and it reacts with the water to form ions?

Answer 4

Ionization

Question 5

What is an example of ionization?

Answer 5

When hydrogen chloride gas is bubbled through and dissolved in water, because it reacts with water to form ions, and then the hydrogen ions and chloride ions separate in solution.

Question 6

Binary Acid Definition

Answer 6

An acid composed of hydrogen and a non-metal/

Question 7

Oxacid Definition

Answer 7

An acid composed of hydrogen, oxygen, and another element.

Question 8

Base Definition

Answer 8

A compound that forms hydroxide ions, OH-(aq), when dissolved in water.

Question 9

True or False: Most common acids and bases form colourless solutions.

Answer 9

True

Question 10

What does determining the pH of a solution help you tell?

Answer 10

Whether an unknown solution contains an acid, a base, or neither.

Question 11

What is the scale that typically ranges from 0 to 14, which is used to classify solutions as acidic, basic, or neutral?

Answer 11

The pH scale

Question 12

pH Scale Definition

Answer 12

A numerical scale ranging from 0 to 14 that is used to classify aqueous solutions as acidic, basic, or neutral.

Question 13

What pH values do acids have?

Answer 13

pH values below pH 7.

Question 14

What does it mean when acids have pH values below pH 7?

Answer 14

There are many more hydrogen ions in the solution than hydroxide ions.

Question 15

True or False: The lower the pH, the more acidic the solution is.

Answer 15

True

Question 16

What have pH values above pH 7?

Answer 16

Bases

Question 17

What do bases having pH values above pH 7 mean?

Answer 17

There are many more hydroxide ions in the solution than hydrogen ions.

Question 18

True or False: The higher the pH, the more basic the solution is.

Answer 18

True

Question 19

What type of solution neither acidic nor basic and falls in the middle of the pH scale at pH 7?

Answer 19

A neutral solution

Question 20

What does a neutral solution having a pH of 7 mean?

Answer 20

There is the same number of hydrogen ions and hydroxide ions in the solution.

Question 21

What are some examples of acidic solutions?

Answer 21

-Stomach Acid
-Lemon
-Grapes
-Tomato
-Banana
-Milk

Question 22

What is an example of a neutral solution?

Answer 22

-Pure Water

Question 23

What are some examples of basic solutions?

Answer 23

-Eggs
-Baking Soda
-Soap
-Ammonia
-Bleach
-Oven Cleaner

Question 24

What happens when an acid and a base are mixed?

Answer 24

They can neutralize each other.

Question 25

What is the reaction of an acid and a base to form a salt and water called?

Answer 25

Neutralization

Question 26

Neutralization Definition

Answer 26

The reaction of an acid and a base to produce a salt and water.

Question 27

True or False: Neutralization can be classified as a type of double displacement reaction.

Answer 27

True

Question 28

What forms as the hydrogen ions of the acid and the hydroxide ions of the base combine?

Answer 28

Water

Question 29

What do the other ions join to form?

Answer 29

A salt

Question 30

True or False: Any ionic compound that is neither an acid or a base can be called a salt.

Answer 30

True

Question 31

In most cases, the salt formed by a neutralization reaction is soluble in water and will not form a _____________.

Answer 31

Precipitate

Question 32

Whether the _______ is added to the ________ or the _______ is added to the _______, the removal of both hydrogen ions and hydroxide ions from solution as they form molecules of water causes the pH of the mixture to approach 7.

Answer 32

Acid; Base; Base; Acid

Question 33

What will the resulting solution be if the right amounts of acid and base react?

Answer 33

Neutral

Question 34

Complete Practice Questions on Page 223, Page 224 (1-2) and Page 227 (1-2); Questions on Page 228, Page 231 and Page 235; Question 1 on Page 238, and Question 1 on Page 246.

Answer 34

Depending on Comfort Level

Question 35

True or False: Acids and bases are two very important classes of chemicals that play an important role in many chemical reactions.

Answer 35

True

Question 36

What Latin word does Acid come from, which means sour?

Answer 36

Acidus

Question 37

What was one of the earliest uses of bases?

Answer 37

Making soap over 5000 years ago in Babylonia

Question 38

Acids react with __________, are _____________, and __________

Answer 38

Metals; Corrosive; Conductive

Question 39

True or False: Acids can turn blue litmus paper red and neutralize bases.

Answer 39

True

Question 40

Why can Acids be useful in the food industry?

Answer 40

Because they act as disinfectants (vinegar and lemon juice) which prevent microorganisms from surviving.

Question 41

True or False: Bases can turn red litmus paper blue and neutralize acids.

Answer 41

True

Question 42

What is a Weak Acid, where are they found, and are they safe to handle? (3 points)

Answer 42

-Acids that are found in household items such as food, drink, and beauty/skincare products -It is safe to handle these acids and even taste them, if they are for eating. -They do not dissociate completely.

Question 43

What is a Strong Acid? ( 2 points)

Answer 43

- Some acids, like those found in a laboratory or a car battery, are very dangerous (too dangerous to touch or taste). -These acids are said to be strong as they can damage other materials by wearing them away.

Question 44

True or False: Both acids and bases can cause severe chemical burns so never touch or taste any unknown chemical.

Answer 44

True

Question 45

When a ____ dissolves in water, the ions separate from one another and hydroxide ions are released into the water in a process called ___________.

Answer 45

Base; Dissociation

Question 46

Many metals react with acids. When this happens the metal fizzes as ________ are produced.

Answer 46

Bubbles

Question 47

When a metal reacts with an acid, the products are a _______ and hydrogen gas.

Answer 47

Salt

Question 48

True or False: The salt produced depends on the metal and type of acid involved in the reaction.

Answer 48

True

Question 49

Many acids are able to conduct electricity so they are ___________.

Answer 49

Conductive

Question 50

Since acids are covalent compounds, they have no _____ to begin with.

Answer 50

Ions

Question 51

But, collisions with __________ ___________ break the acid molecule apart into its respective ions.

Answer 51

Water Molecules

Question 52

Bases are substances that conduct electricity and can change the colour of ______ ________ _______

Answer 52

Acid-Base Indicators

Question 53

What do Bases feel and taste like?

Answer 53

They feel slippery and taste bitter (even though most should not be tasted).

Question 54

What is a Weak Base? (2 Points)

Answer 54

- Bases that are found in soaps and other materials used for cleaning. -It is safe to handle these bases, which can feel soapy; these are known as weak bases.

Question 55

What is a Strong Base? (2 Points)

Answer 55

-Some bases, like those in a laboratory or cleaning materials, are too dangerous to touch. -These bases are said to be strong because they can burn skin and damage other materials.

Question 56

What does it mean when bases are conductive?

Answer 56

They are good conductors of electricity.

Question 57

True or False: Most bases are ionic compounds, so they are made of ions (unlike acids)

Answer 57

True

Question 58

Several natural chemicals and many synthetic (human-made) chemicals _____ _______ when they are placed in acidic or basic solutions

Answer 58

Change Colour

Question 59

What is a substance that changes its colour depending on the pH of the solution known as?

Answer 59

An acid-base indicator

Question 60

True or False: Litmus is a special type of paper treated with a specific indicator that tests for acidity/basicity

Answer 60

True

Question 61

What is an electronic pH Meter used for? (2 points)

Answer 61

-To determine the pH of a solution. -These meters use the electrical properties of a solution to determine pH.

Question 62

pH Indicator Definition

Answer 62

A substance that changes colour to show the concentration of hydrogen ions and hydroxide ions in a solution.

Question 63

True or False: In a neutral solution, neither red nor blue litmus paper changes colour.

Answer 63

True

Question 64

To more accurately determine the ____ of. a solution, several indicators that cover the pH range between pH 0 and pH 14 must be used.

Answer 64

pH

Question 65

What is universal indicator?

Answer 65

A mixture of several indicators that produce a different colour at different pH values.

Question 66

How is the pH paper prepared?

Answer 66

By soaking strips of paper in universal indicator and then allowing them to dry?

Question 67

True or False: A drop of solution to be tested in placed on the pH paper. The resulting colour is compared against a colour chart to determine the pH of the solution.

Answer 67

True