(Chapter 3.2) Chemical Reactions: Classifying Reactions

Question 1

Identify the properties of acid

Answer 1

Acids taste sour, have a pH level lower than 7, are corrosive, forms hydrogen ions in water, and have at least 1 hydrogen atom.

Question 2

Identify the properties of bases

Answer 2

Bases taste bitter, are corrosive, forms hydroxide in water, and have a pH level higher than 7

Question 3

Identify the colour(s) produced by acids when tested on the universal indicator

Answer 3

Red, orange, yellow, and lighter shades of green

Question 4

Identify the colour(s) produced by bases when tested on the universal indicator

Answer 4

Darker shades of green, blue, and purple

Question 5

Identify the colour(s) produced by acids when tested on litmus paper

Answer 5

Red

Question 6

Identify the colour(s) produced by bases when tested on litmus paper

Answer 6

Blue

Question 7

Identify the colour(s) produced by neutral substances when tested on the universal indicator

Answer 7

Green

Question 8

Identify the colour(s) produced by neutral substances when tested on litmus paper

Answer 8

Red or blue depending on the litmus paper used as neutral resulted in no colour change

Question 9

Identify the reactant(s) and product(s) in a neutralisation reaction

Answer 9

Reactants: Acid + Base (where the avergae of the pH level of the 2 substances is 7)
Products: Salt + Water

Question 10

Define alkali

Answer 10

A base that dissolves in water

Question 11

Identify the product(s) of a reaction between acid + metal

Answer 11

Salt + Hydrogen Gas

Question 12

Identify the product(s) of a reaction between acid + metal carbonate

Answer 12

Salt + Carbon Dioxide + Water

Question 13

Define rusting

Answer 13

The chemical process of the corrosion of iron or steel

Question 14

What is corrosion and how does it occur?

Answer 14

Corrosion is the decay of metal as a result of contact with water (moisture) and/or oxygen

Question 15

What is the simplest method to measure the pH level of gases?

Answer 15

Dissolve the gas in distilled water and then measure the pH level of the mixture

Question 16

Define acidic oxide

Answer 16

An oxide that produces an acidic solution when dissolved in water.

Question 17

Define combustion

Answer 17

The chemical process in which a substance (fuel) reacts with oxygen and releases heat energy

Question 18

Identify the possible product(s) from a chemical reaction between hydrocarbon + oxygen

Answer 18

Carbon Dioxide + Water
Carbon Monoxide + Water
Carbon (as soot) + Water

Question 19

What element(s) does hydrocarbons consist of?

Answer 19

Hydrogen and carbon

Question 20

What element(s) does carbohydrates consist of?

Answer 20

Hydrogen, carbon, and oxygen

Question 21

What is the difference between a displacement and replacement reaction?

Answer 21

There is no difference

Question 22

Can a double-displacement reaction occur between 2 covalent compounds?

Answer 22

Yes, however it is rare.

Question 23

Using letters as substitution for the anion and cation in the compounds, illustrate a single-displacement reaction

Answer 23

AB+C –> AC+B

Question 24

Using letters as substitution for the anion and cation in the compounds, illustrate a double-displacement reaction

Answer 24

AB+CD –> AD+CB

Question 25

Using letters as substitution for the anion and cation in the compounds, illustrate a decomposition reaction

Answer 25

AB –> A+B

Question 26

Define amphoteric

Answer 26

A compound that can react as an acid or base

Question 27

Identify the product(s) and reactant(s) in a corrosion reaction

Answer 27

Reactants: Metal + Oxygen + Water
Products: Metal Oxide + Hydroxide

Question 28

Do metal oxides tend to be basic or acidic?

Answer 28

Basic

Question 29

Do non-metal oxides tend to be basic or acidic?

Answer 29

Acidic

Question 30

Define electronegativity

Answer 30

The ability of an atom to attract to itself an electron pair shared with another atom in a chemical bond

Question 31

Define a polar bond

Answer 31

A type of covalent bond, between 2 atoms, in which electrons are shared unequally

Question 32

Define a non-polar bond

Answer 32

A type of covalent bond, between 2 atoms, in which electrons are shared equally

Question 33

Describe the trend of electronegativity of elements

Answer 33

Elements are more electronegative on the top and right so it is a positive trend

Question 34

What difference in the value of electronegativity is considered a non-polar bond?

Answer 34

0 - 0.4

Question 35

What difference in the value of electronegativity is considered a polar bond?

Answer 35

0.4 - 1.7

Question 36

What difference in the value of electronegativity is considered an ionic bond?

Answer 36

1.7 - 3.3

Question 37

Explain why a polar bond is closer in the difference in the value of electronegativity to an ionic bond than a non-polar bond

Answer 37

In an ionic bond, electron(s) are ‘donated’ to another element and unequal sharing is closer to donation than equal sharing

Question 38

Define dipole

Answer 38

A bond or molecule, with 2 oppositely charged ends/poles

Question 39

Define dipole moment

Answer 39

A measurement of the separation of 2 opposite electrical charges

Question 40

Explain why metal oxides are basic

Answer 40

When metal oxides are dissolved in water, it forms a substance with hydroxide, a property of basic substances

Question 41

Explain why non-metal oxides are acidic

Answer 41

When non-metal oxides are dissolved in water, it forms a substance with hydrogen, a property of acidic substances