alcohols

Question 1

what are alcohols?

Answer 1

organic molecules containing an OH- functional group

Question 2

what does the start of the name show?

Answer 2

the number of carbon atoms it has

Question 3

what does the end of the name show?

Answer 3

-ol to show its an alcohol `

Question 4

what are the 3 main categories of formula used to represent alcohols on paper?

Answer 4

molecular formula
structural formula
displayed formula

Question 5

what does the molecular formula show?

Answer 5

just each element, only once
doesn’t show the structure of the molecule at all

Question 6

what does the displayed formula show?

Answer 6

each atom and every bond drawn out
perfectly shows the structure of the molecule

Question 7

what are the 2 methods to make ethanol?

Answer 7

hydration of ethene
fermentation of glucose

Question 8

in hydration of ethene, what is ethene mixed with?

Answer 8

steam

Question 9

what are the conditions for the hydration of ethene?

Answer 9

300 degrees celsius
65 atm pressure
phosphoric acid (H3PO4) catalyst

Question 10

what raw material provides the ethene in the hydration of ethene?

Answer 10

crude oil

Question 11

what are the advantages of the hydration of ethene?

Answer 11

makes pure ethanol
can run continously

Question 12

what are the disadvantages of the hydration of ethene?

Answer 12

conditions require lots of energy
non- renewable raw material used

Question 13

what happens in the fermentation of glucose?

Answer 13

glucose is fermented microbiologically under the following conditions:
yeast- provides enzymes
30 degrees celsius- enzymes optimum temperatures
anaerobic- prevents oxidation

Question 14

what raw material in the fermentation of glucose provides the glucose?

Answer 14

sugar cane

Question 15

what are the advantages of the fermentation of glucose?

Answer 15

renewable raw material used
conditions not energy intensive

Question 16

what are the disadvantages of the fermentation of glucose?

Answer 16

makes impure ethanol
must be done in individual batches

Question 17

what are the 3 ways ethanol can be oxidised?

Answer 17

combustion
microbial oxidation
chemical oxidation

Question 18

why does ethanol combust completely?

Answer 18

because of the oxygen atom in the OH- group

Question 19

what flame does the combustion of ethanol have?

Answer 19

a non-luminous, blue flame

Question 20

formula for combustion of ethanol?

Answer 20

C2H5OH + 3O2 -> 2CO2 + 2H2O

Question 21

what do micro-organisms use to oxidise ethanol into ethanoic acid?

Answer 21

the oxygen in the air

Question 22

under what conditions can microbial oxidation happen?

Answer 22

aerobically- if the microorganism is growing in the presence of air

Question 23

what does the (O) show?

Answer 23

the microbial use of oxygen in an equation

Question 24

what is the equation for microbial oxidation?

Answer 24

C2H5OH + 2(O) -> CH3COOH + H2O

Question 25

what do we use when we want to deliberately oxidise ethanol in the lab?

Answer 25

we heat it with a mixture of:
potassium dichromate (VI) (K2Cr2O7)
dilute sulphuric acid (H2SO4)

Question 26

what does chemical oxidation form?

Answer 26

ethanoic acid

Question 27

what is the formula for chemical oxidation?

Answer 27

C2H5OH + 2(O) -> CH3COOH + H2O

Question 28

what are the orange dichromate (VI) ions turned into?

Answer 28

green chromium (III) ions