organic chem

Question 1

use of paraffin oil

Answer 1

fuel for heating and cooking and for aircraft

Question 2

general formula of alcohol

Answer 2

CnH2n+1OH

Question 3

use of naphtha

Answer 3

feedstock for chemical industry

Question 4

general formula of alkane

Answer 4

CnH2n+2

Question 5

general formula of carboxylic acid

Answer 5

CnH2n+1COOH

Question 6

define homologous series

Answer 6

a family of organic compounds with a general formula, having similar chemical properties and showing a gradation in physical properties

Question 7

does boiling point increase/decrease down the series?

Answer 7

increase

Question 8

use of diesel oil

Answer 8

fuel for diesel engines

Question 9

how many carbon in prop

Answer 9

3

Question 10

use of petrol

Answer 10

fuel in cars

Question 11

use of lubricating oil

Answer 11

lubricants, making waxes and polishes

Question 12

physical state of alkane and alkene

Answer 12

gas

Question 13

use of petroluem

Answer 13

fuel for cooking

Question 14

how many carbon in eth

Answer 14

2

Question 15

use of bitumen

Answer 15

making road surfaces

Question 16

does density increase/decrease down the series?

Answer 16

increase

Question 17

does flammability increase/decrease down the series?

Answer 17

decrease

Question 18

how many carbon in meth

Answer 18

1

Question 19

what test is used to differentiate alkane and alkene?

Answer 19

bubble the gas through aqueous bromine

Question 20

what colour change is observed when aqueous bromine is added to an alkene

Answer 20

aqueous bromine changes from reddish brown to colourless

Question 21

what colour change is observed when aqueous bromine is added to an alkane

Answer 21

aqueous bromine remains reddish brown

Question 22

does viscosity increase/decrease down the series?

Answer 22

increase

Question 23

general formula of alkene

Answer 23

CnH2n

Question 24

what is a functional group?

Answer 24

an atom or group of atoms that gives a molecule its characteristic properties

Question 25

what is the functional group of alkane

Answer 25

no functional group

Question 26

what is the functional group of alkene

Answer 26

carbon carbon double bond (- c=c -)

Question 27

what is the functional group of alcohol

Answer 27

hydroxyl group (O-H)

Question 28

what is the functional group of carboxylic acid

Answer 28

carboxyl group O II —C —O—H

Question 29

are alkanes saturated or unsaturated

Answer 29

saturated

Question 30

are alkenes saturated or unsaturated

Answer 30

unsaturated

Question 31

products formed when alkanes and alkenes burn completely in oxygen (complete combustion)

Answer 31

carbon dioxide and water

Question 32

products formed when alkanes and alkenes burn in insufficient oxygen

Answer 32

soot and carbon monoxide

Question 33

define substitution reaction

Answer 33

a hydrogen atom in an alkane is replaced by a halogen atom

Question 34

define addition reaction

Answer 34

a reaction in which an UNSATURATED organic compound combines with another substance to form a SINGLE new compound

Question 35

what kind of reaction is (methane + chlorine) ?

Answer 35

substitution reaction

Question 36

products formed when (methane + chlorine )

Answer 36

chloromethane and hydrogen chloride

Question 37

conditions needed for substitution reaction

Answer 37

sunlight/ultraviolet light

Question 38

ethene + hydrogen is what kind of reaction

Answer 38

addition reaction with hydrogen (hydrogenation) coverts unsaturated to saturated compound

Question 39

products formed when ethene + hydrogen

Answer 39

ethane

Question 40

define monomer

Answer 40

small molecules of alkene

Question 41

define polymer

Answer 41

long chain molecule formed when alkene molecules join together

Question 42

conditions needed for addition polymerisation of alkenes

Answer 42

-high temperature (600 °C) -high pressure -presence of catalyst

Question 43

advantages of plastics | there are 5

Answer 43

- easily molded into different shapes - waterproof -durable -corrosion resistant -complete combustion of plastic produce CO2 + H20, hence no solid residue is formed minimising waste produced

Question 44

disadvantages of plastics | there are 3

Answer 44

-flammable -produces poisonous gas (eg. CO) when burned hence contributing to air pollution -non biodegradable (have to dispose in landfills which takes up space and causes land pollution)

Question 45

can polymers conduct electricity? why or why not?

Answer 45

polymers CANNOT conduct electricity because it is a covalent molecule and has NO IONS to carry electric current

Question 46

define cracking

Answer 46

breaking down of long chain hydrocarbons into smaller molecules

Question 47

describe process and conditions needed for cracking of petroleum

Answer 47

1. pass the petroleum fraction containing long chain alkanes over a heated catalyst at about 600 °C 2. catalysts are aluminium oxide and silicon dioxide

Question 48

importance of cracking | there are 3

Answer 48

- to produce short chain alkenes such as ethene and propene used for making ethanol and plastics - to produce hydrogen - to produce petrol used as fuel for cars

Question 49

why can alkenes be polymerized?

Answer 49

alkene contains c=c double bonds that can be broken and more atoms can be added to it

Question 50

physical state of alcohol and carboxylic acid

Answer 50

liquid

Question 51

what temperature is the mixture kept at during fermentation of glucose?

Answer 51

37 °C

Question 52

why must the mixture be kept at 37 °C during fermentation of glucose?

Answer 52

beyond 37 °C -> enzyme will denature below 37 °C-> fermentation will slow down

Question 53

conditions for fermentation of glucose

Answer 53

- catalyst: yeast - temp at 37 °C -absence of oxygen

Question 54

conditions needed for oxidation of ethanol

Answer 54

warm the mixture of ethanol + acidified potassium manganate (VII)