inorganic chem flash - purple (use written notes)

Question 1

what is an isomer

Answer 1

An isomer is a molecule with the same molecular formula but different structural formula

Question 2

What is a stereoisomers

Answer 2

A stereoisomer is when the order of bonding in each atom is the same but the spatial arrangement of the atom is different in each bond

Question 3

What are geometric isomers

Answer 3

A geometric isomer occurs when the arrangement of the atom is different in each isomer

Question 4

Under what circumstances do geometric isomers occur

Answer 4

Occur when there is rotation around a carbon to carbon double bond, also there must be two different groups attached to each of the carbon atoms that make up the bond

Question 5

What is meant by cis and trans

Answer 5

Cis is groups on the sdame side of the double bond, trans is groups on opposite side of the double bond

Question 6

How do properties of geometric isomers differ

Answer 6

Geometric isomers can have different physical properties

Question 7

What are optical isomers

Answer 7

they are non-super imposable mirror images

Question 8

When do optical isomers occur

Answer 8

When four different groups are arranged vertically around a central carbon atom (chiral carbon)

Question 9

How do properties of optical isomers occur

Answer 9

Identical but on light

Question 10

Effect of enantiomers on polarise light

Answer 10

One enantiomer will rotate light in one direction and the other enantiomer in the opposite direction by the same difference. as there is an equal amount of each enantiomer, the rotation would cancel

Question 11

What is a racemic mixture and why are they described as being optically inactive

Answer 11

A racemic mixture is one that has equal amounts of left and right handed enantiomers, of a chiral molecule

Question 12

what is nucleophilic substitution reaction

Answer 12

A nucleophilic substitution is when a nucleophile substitutes itself for the halogen atom, this can occur because the positive charge on carbon atom due to polar bonds makes it act like an electrophile

Question 13

What are the different mechanisms for a nucleophilic substitution reaction

Answer 13

There are two mechanisms for nucleophilic substitution reactions. SN1 and SN2

Question 14

Talk about SN1 mechanism

Answer 14

The SN1 mechanism is a two step process. Step 1 is the slow rate determining step, the haloalkane undergoes heterolytic fission to form a carbocation intermediate. Step 2 is the first step and it involves nucleophilic attack on the carbocation by a nucleophile.

Question 15

Talk about SN2 mechanism

Answer 15

The SN2 mechanism involves only one continuous step. The nucleophile attacks the carbon atom from the side opposite the carbon to halogen bond and begins to form a covalent bond with it. At the same time the carbon to halogen Bond begins to break. A transition state is reached, this adapts a trigonal known bipyramidal structure. The reaction is complete by the formation of our fill new bond and the complete break up of the carbon to halogen bond

Question 16

How can the mechanism for Nucleophilic substitution be determined

Answer 16

In SN1 mechanism, a carbocation Intermediate is formed and this could be a primary, secondary or tertiary Carbocation. Alkyl groups have a positive effect. This means they are electron donating And can push electrons onto the positively charged carbon atom. Therefore it follows that tertiary carbocations are the most stable. This supports that tertiary haloalkanes are most likely to react with a nucleophile In an SN1 mechanism.

Question 17

What are factors affecting SN1 mechanism

Answer 17

The size of the alkyl groups in the haloalkane Is important, this is known as the something effect. In an SN2 mechanism THE NUCLEOPHILE Attacks the carbon atom from the opposite side of the halogen atom. In tertiary haloalkanes, attack from the side is likely to be hindered because the alkyl groups Will limit access to the carbon atom. Primary haloalkanes I have no more than one alkyl. Group attached to the halogen carbon atom and sort access to the carbon atom will be much easier therefore primary haloalkanes react with nucleophiles in SN2 mechanisms

Question 18

What are factors affecting SN2 mechanism

Answer 18

The stability of the Carbocation is very important

Question 19

What are the different types of reactions that involve haloalkanes

Answer 19

The size of the alkyl group is very important (steric effect)

Question 20

Talk about elimination reactions of haloalkanes

Answer 20

Halo alkanes can undergo elimination Reactions when they are heated under reflux with potassium hydroxide or sodium hydroxide. In the formation of the carbon to carbon double bond the carbon atom, together with a hydrogen atom on an adjacent carbon atom, has been removed or eliminated from the halo alkanes and not replaced, this reaction is known as base induced elimination

Question 21

Alkenes can be prepared by dehydration of alcohols using aluminium oxide, conc sulfuric acid or conc phosphoric acid. They can also be prepared by base-induced elimination (propan-1-ol to propene)

Answer 21

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Question 22

Makovniovs rule

Answer 22

is that when a hydrogen halide or water is added to an asymmetric alkene, the hydrogen atom becomes attached to the carbon with the most hydrogen atoms attached to it already. During the reaction of a hydrogen halide or water with alkenes, markovnikov’s rule is used to predict the major and minor products formed.

Question 23

Alkenes take part in electrophilic addition reactions with:hydrogen to form alkanes in the presence of a catalyst and halogens to form dihaloalkanes.

Answer 23

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Question 24

haloalkanes can undergo addition reactions with halogen to form haloalkanes

Answer 24

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Question 25

haloalkanes a hydration reaction with water using an acid catalyst to form alcohols. This is also an addition reaction

Answer 25

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Question 26

Haloalkanes are substituted alkanes where one or more of the hydrogen atoms is substituted with a halogen atoms

Answer 26

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Question 27

Mono Haloalkanes contain only one halogen atom. They can be classified as primary,secondary or tertiary according to the number of alkyl groups attached to the carbon atom bonded to the halogen atom

Answer 27

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Question 28

haloalkanes take part in elimination reactions to form alkenes using a strong base, such as sodium or potassium hydroxide in an ethanol solvent

Answer 28

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Question 29

Mono Haloalkanes take part in nucleophilic substitution reaction with: aqueous alkalis to form alcohols, and alcoholic alkoxides to form ethers

Answer 29

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Question 30

Haloalkanes undergo either sn1 or sn2 mechanism reactions

Answer 30

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Question 31

Alcohols can be prepared from:
Haloalkanes by substitutions
Alkenes by acid-catalysed hydration
Aldehydes and ketones undergo a reduction using lithium aluminium hydride as a reducing agent
Carboxylic acids prepared with acidified permanganate

Answer 31

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Question 32

Primary amines have nh2 and an r group, secondary have nh and two r groups, tertiary amines have 3r groups.

Answer 32

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Question 33

Amines react with acids to form salts

Answer 33

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Question 34

Primary and secondary amines have tertiary bonding, so bp is higher

Answer 34

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Question 35

Amines are weak bases. The nitrogen atom had a lone pair of electrons which can accept a proton from water.

Answer 35

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Question 36

Secondary and primary amines become less soluble as chain length increases

Answer 36

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Question 37

Tertiary amines with low molecular mass are soluble in water

Answer 37

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Question 38

The stronger the base the higher the pka value

Answer 38

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Question 39

Benzene is the simplest member of the class of aromatic hydrocarbons

Answer 39

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Question 40

benzene cant take part in addition reactions

Answer 40

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Question 41

benzene has Sp2 hybridisation

Answer 41

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Question 42

in benzene If something has been substituted one of the hydrogens its known as phenyl

Answer 42

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Question 43

Molecules that have the same molecular formula but different structural formulae are called isomers.

Answer 43

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Question 44

Stereoisomers are when the order of bondinging in the atoms is the same but the spatial arrangement of the atoms is different in each isomer. There are two types of stereoisomers:geometric and optical.

Answer 44

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Question 45

when do geometric isomers occur

Answer 45

Occur when there is restricted rotation around a carbon to carbon double bond

Question 46

facts about geometric isomers

Answer 46

Have two different groups attached to each of the carbon atoms that make up the bond with restricted rotation

Cis or trans

Differences in melting and boiling points

Different chemical properties

Question 47

optical isomers Occur in compounds in which four different groups are arranged tetrahedrally around a central carbon atom

Answer 47

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Question 48

facts about optical isomers

Answer 48

Non superimposable images of each other

Can be described as enantiomers

Identical properties

Form racemic mixtures when enantiomers are in equal volume

Enantiomers are basically two super imposable images of each other

Question 49

state makovnikovs rule

Answer 49

Markovnikov’s rule states that when a hydrogen halide or water is added to an unsymmetrical alkene, the hydrogen atom becomes attached to the carbon with the most hydrogen atoms attached to it already. Markovnikov’s rule can be used to predict major and minor products formed during the reaction of a hydrogen halide or water with alkenes.