Chapter 14 Intro into Organic chemistry

Question 1

Hydrocarbons

Answer 1

are compounds that are made up of carbon (C) and hydrogen (H) atoms ONLY

Question 2

A functional group

Answer 2

is an atom or a group of atoms in an organic molecule, which determines the physical and chemical properties of the molecule

Question 3

Alkanes

Answer 3

are the simplest hydrocarbons with no functional group -They are made up of carbon and hydrogen atoms bonded to each other with single covalent bonds

Question 4

Functional Groups of Organic Compounds

Answer 4

-Functional groups determine the physical and chemical properties of molecules R is any other atom or group of atoms (except for hydrogen)

Question 5

The general formula is

Answer 5

is a formula that represents a homologous series of compounds using letters and numbers -A homologous series is a group of organic compounds that have the same functional group, the same general formula and the same chemical properties Eg. the general formula of alkanes is CnH2n+2

Question 6

The skeletal formula is

Answer 6

a simplified displayed formula with all the carbon and hydrogen (C-H) bonds removed

Question 7

The displayed formula is

Answer 7

a 2D representation of an organic molecule showing all its atoms (by their symbols) and their bonds (by single, double or triple bonds)

Question 8

The structural formula is

Answer 8

a formula that shows how the atoms are bonded to each carbon atom in a molecule

Question 9

Systematic nomenclature can

Answer 9

be used to name organic compounds and therefore make it easier to refer to them

Question 10

The molecular formula

Answer 10

shows the number and type of each atom in a molecule Eg. the molecular formula of ethanoic acid is C2H4O2

Question 11

The empirical formula

Answer 11

shows the simplest whole number ratio of the elements present in one molecule of the compound Eg. the empirical formula of ethanol is CH2O

Question 12

Homologous series

Answer 12

A homologous series is a group of organic compounds that have the same functional group, the same general formula and the same chemical properties

Question 13

Saturated hydrocarbons

Answer 13

are hydrocarbons which contain single bonds only resulting in the maximum number of hydrogen atoms in the molecule

Question 14

Unsaturated hydrocarbons

Answer 14

are hydrocarbons which contain carbon-carbon double or triple bonds

Question 15

Homolytic fission

Answer 15

is breaking a covalent bond in such a way that each atom takes an electron from the bond to form two radicals

Question 16

Heterolytic fission

Answer 16

is breaking a covalent bond in such a way that the more electronegative atom takes both the electrons from the bond to form a negative ion and leaving behind a positive ion

Question 17

The diagram shows heterolytic fission in which the most electronegative atom takes both electrons in the covalent bond and homolytic fission in which each atom takes one electron from the covalent bond

Answer 17

Question 18

Radical chain reactions

Answer 18

A free radical is a species with one (or more than one) unpaired electrons

Question 19

A free radical reaction is a reaction involving

Answer 19

• Initiation is the first step and involves breaking a covalent bond using energy from ultraviolet (UV) light from the sun to form two free radicals
• The propagation step is the second step in which the formed radical can attack reactant molecules to form even more radicals
• These in turn can again attack other molecules to form more free radical and so on
• In the termination step, two free radicals react together to form a product molecule

Question 20

A nucleophile

Answer 20

is an electron-rich species that can donate a pair of electrons

‘Nucleophile’ means ‘nucleus/positive charge loving’ as nucleophiles are attracted to positively charged species

Nucleophilic refers to reactions that involve a nucleophile

Question 21

An electrophile

Answer 21

-is an electron-deficient species that can accept a pair of electrons

‘Electrophile’ means ‘electron/negative charge loving’ as electrophiles are attracted to negatively charged species

-Electrophilic refers to reactions that involve an electrophile

Question 22

An addition reaction

Answer 22

is an organic reaction in which two (or more) molecules combine to give a single product with no other products

Question 23

A substitution reaction

Answer 23

is a reaction that involves replacing an atom or group of atoms by another

Question 24

An elimination reaction

Answer 24

is a reaction in which a small molecule (such as H2O or HCl) is removed from an organic molecule

Question 25

A hydrolysis reaction

Answer 25

is a reaction in which a compound is broken down by water (it can also refer to the breakdown of a substance by dilute acids or alkali)

Question 26

A condensation reaction

Answer 26

is a reaction in which two organic molecules join together and in the process eliminate small molecules (such as H2O or HCl)

Question 27

An oxidation reaction

Answer 27

• is a reaction in which oxygen is added, electrons are removed or the oxidation number of a substance is increased
• In organic chemistry it often refers to the addition of oxygen or removal of hydrogen atoms to a substance
• In equations for organic redox reactions, the symbol [O] can be used to represent one atom of oxygen from an oxidising agent

Question 28

A reduction reaction

Answer 28

• is a reaction in which oxygen is removed, electrons are added or the oxidation number of a substance is decreased
• In organic chemistry it often refers to the removal of oxygen or addition of hydrogen atoms to a substance
• In equations for organic redox reactions, the symbol [H] can be used to represent one atom of hydrogen from a reducing agent