C10 - Organic Reactions

Question 1

-Alkenes molecules contain a double bond between the carbon atoms .

Answer 1

-Because of the double nomd , alkanes all react in a SIMILAR WAY .
-Scientists call the odubel bond - THE ALKENE FUNCTIONAL GROUP .

Question 2

Meaning of functional group

Answer 2

Part of the molecule that determeines how it reacts .
-All alkenes have the SAME functional group (carbon to carbon double bond )

Question 3

-Scientists call molecules sucha s alkenes a homologous series .

Answer 3

-Members of a homologous seriees all have the SAME FUNCTIONAL GROUP .
-Each molecule in a homologous series has an EXTRA CARBON ATOM +TWO EXTRA HYDROGEN ATOMS .

Question 4

Learn the reactions for alkenes and the conditions

Answer 4

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Question 5

1. Combustion of alkenes (burns )

Answer 5

-When we combust alakanes we porduce carbondioxide and water , this is also true when we combust alkenes .

-HOWEVER , combusting an alkenee also produces unburnt carbon particles . That is because of INCOMPLETE COMBUSTION , menaing alkenees burn in air with a smoky flame .

Question 6

-Alkenes reaction with hydrogen
(Check sheet)

Answer 6

-Known as HYDROG
-conditions for this reaction - REQUIRES A TEMPERATURE OF 150 DEGREES AROUND
-We also need a NICKEL CATALST - to speed up the reaction . .

Question 7

Hydrogenation reaction explained

Answer 7

-In this reaction , the two hydrogen atoms add across the double bond .
-The carbon to carbon double bond is converted iNTO A CABON TO CARBON singl ebond .
-In e.g - ethene has to be converted into the alkane ethane
-SO REACITNG AN ALKENE WITH HYDROGEN PRODUCES AN ALKENE .

Question 8

Reaction of alkekens with water is called HYDRATION
(check sheet )

Answer 8

CONDITIONS OF RHYDRATION
-Water must bei nt he form of steam .
-The temperature must be aroudn 300 degrees .
-Pressure around 70 atmospheres .
-We can also use phosphoric acid as a catalyst to speed up the reaction .

Question 9

The reactions is reversible …

Answer 9

-SO to increase the yield of ethnol , any unreacted ethene and steam are passed back through the ctalsst .

Question 10

This reaction might appear as a REVERSIBLE REACTIOn , in the exam .

Answer 10

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Question 11

-Reaction of alkenes with Halogesn , Chlorine , Bromine , and Iodine .

Answer 11

-Alkenes react quiet rapidlyw ith Halogens .

Question 12

Reaction with Chorien (check book)

Answer 12

-The two chlorine aotms int he chlorine molecule have added acroos the double bond .
-The oduble carbon to carbon bond have now turned into a single carbon to carbon bond .

Question 13

Bromine …
-Iodine …

Answer 13

Dibromoethane
-Diodoethane

Question 14

Uses of alkenes

Answer 14

-fuels
-Solvents
-Alcholic drinks

Question 15

The alchohols are a homologous series (same funcitonal group)

Answer 15

which is OH .
CH3OH strcutral FORMULA for methanol .

Question 16

Need to know the name and strcuture for the first FOUR ALCHOLS

Answer 16

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Question 17

STRUCTURE OF METHANOL

Answer 17

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Question 18

STRUCTURE OF ETHANOL

Answer 18

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Question 19

STRUCTURE OF PROPONAL

Answer 19

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Question 20

STRUCUTRE OF bUGTANOL

Answer 20

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Question 21

ONE way of making alcohol

Answer 21

-Hyddration of Ethene .
-LOOKA AT LAST SHEET FORMULA

Question 22

Advanatage of using hydration of ethene to make alcohol

Answer 22

-Reaction produces a high yeld of ethanol .

Question 23

Disadvanatage of using hydration of ethene to make alcohol .

Answer 23

-Reaction reqruies a high temperature in other words - A LOT OF ENERGY ,
-Ethene for thi reaction comes from CRUDE OIl , this is nonrenewable .

Question 24

ANOTHER WAY of making

Answer 24

-Fermentatiion of suagr .
-CHECK REACTION ON SHEET .
-In fermentation we start wuth a sugar solution such as glucose and we mix thris with yeast .
-The yeast converts to the sugar solution to a solution of ethnaol . Carbondioxide gaas is also produced .

Question 25

What are the conditions of fermentation ?

Answer 25

-The temperature should be around 30 degrees . -The reaction must take place in anaerboic conditions (without oxygen ) .

Question 26

Advanatage of fermentation to make alcohol ?

Answer 26

-The low temperature means that the reaction does not require a lot of energy . -The sugar for this reaction comes from plants and therefore , is renewable .

Question 27

Dsadvanatage of fermentation to make alcohol ?

Answer 27

-The product is an aqueous solution of ethanol . (Ethanol dissolved in water) . -We need to PURIFY ehtanol by distillaiton and that requires energy .

Question 28

Alcohols solubility in water

Answer 28

-Alchoks are soluble in water and form neutral solutions . -As the numebr sof carbon atoms increases the SOLUBILTITY DECREASES .

Question 29

1.Reaction with sodium (check sheet)

Answer 29

-Int his reaction we see bubbles of hydorgen gas being produced . -We also make the product sodium ethoxide . (same reaction for methanol ,ethanol and propanol and butanol , first THREE letters of each alocohol and add 'oxide')

Question 30

ReEACTION WITH oxidising agents (check sheet )

Answer 30

- good example of an oxidising agent is ACIDIFIED POTASSIUM DICHROMATE . -When alchools react with oxidising agents , they produce CARBOXYLIC ACID +WATER . (same reaction with other four alchosl first four letters add 'oic' and acid')

Question 31

Reaction with combustion

Answer 31

-Alchols release energy when combusted . -Combusitng a n alochol in air produces carbondioxide+water . check sheet and also balancing equations

Question 32

If we react an alcohol with an oxidising agent ?

Answer 32

-We produce a carboxylic acid .

Question 33

Carboxlic acids

Answer 33

-are a homologous serious , they all have the same fucnitonal group -COOH

Question 34

-Rather than drawing the individual atoms and bons , scientists rather use a structural formulas .

Answer 34

-Learn the Chemical formulas .

Question 35

These acids will be from smallest to biggest

Answer 35

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Question 36

Chemical and structural formula for methanoic aicd

Answer 36

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Question 37

Chemical and structural formula for ethanoic acid

Answer 37

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Question 38

Chemical and structural formula for propanoic acid

Answer 38

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Question 39

Chemical and strucutral formual ofr butaanoic acid .

Answer 39

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Question 40

Dissolving carboxylic acids in water

Answer 40

check sheet for equation

Question 41

-In water , carboxylic acids are weak acids

Answer 41

-Ethanoic acid is ionising to produce the ehtanotate ionand H+

Question 42

What type of reaction is dissolving carboxylic acids in water

Answer 42

-This is a reversible reaction ; ethanoate ion and H+ can resemble to form ethanoic acid .

Question 43

Why are carboxylic acids known as WEAK ACIDS ?

Answer 43

-As the carboxlic aicds onl partially ionse in aqueous solutions , they are Weak acids . --Meaning carboxlic acids have a HIGHER pH than a strong acid such as hydrochloric acid .

Question 44

Carboxylic acids reactng with metal carbonate

Answer 44

check sheet for equation .

Question 45

Carboxylic acids reactng with metal carbonate EXPLAINED check sheet and online ofr the other two carboxlic acids -Get begginign of acid and stick'ate' to it .

Answer 45

-We have made the salt sodiume thnaote and carbondioxide gas +water / (all carboxylic acids react like this with emtl carbonates .)

Question 46

Reaction of carboxylic acids with alcohols . -check sheet for equation and learn .

Answer 46

-When we react carboxylic acid with an alcohol , we make a molecule called an ester . WE ALSO MAKE WATER . -eSTERS ARE REALLY useful molecules , as they often have a plesant smell (used in perfumes) .

Question 47

Key points about the reaction

Answer 47

-The reaction requires a sulfuric acid catalyst . -It is a reversile reaction , so you can seeit in a quetion for reversible reactions .