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A LEVEL CHEMISTRY PAPER 1 > Organic > Flashcards

Flashcards in Organic Deck (33):
1

Identify the characteristic of the haloalkane molecule that enables it to undergo a nucleophillic substitution reaction: (Eg in bromo-propane) SPECIFIC

The Polar C-Br bond.

2

Give a condition needed to favour an elimination reaction in a halogenoalkane rather than a nucleophillic substitution reaction:

-High temperature

3

Give a use for sulfur dioxide that is formed as a byproduct in a reaction:

To make gypsum / plaster
OR to make H2SO4

4

Identify one feature of the infrared spectrum which supports the fact that this is an
alcohol. You may find it helpful to refer to Table 1 on the Data Sheet.
Explain how infrared spectroscopy can be used to identify this isomeric alcohol. (3 Marks)

-Peak at 3230-3550
-Run the infrared spectra (of the alcohols)
-Find the one that matches this spectrum
OR
-Peak at 3230-3550
-Use fingerprint region
-And match with spectra in database

5

Butan-1-ol reacts with acidified potassium dichromate(VI) solution to produce two organic compounds.
Name the two compounds that form.

Butanoic acid CH3CH2CH2COOH

Butanal CH3CH2CH2CHO

6

When chlorine gas dissolves in cold water a pale green solution is formed.
CL2(g) +H20(l) --> H+ + Cl- + HClO
Give the formula of the species responsible for the pale green colour in the solution of chlorine in water.

Cl2

7

When chlorine reacts with water in BRIGHT sunlight, only two products are formed.
One is a colourless, odourless gas and the other is an acidic solution that reacts with silver nitrate solution to give a white precipitate.
Name the two products.

Colourless, odourless gas- O2

Acidic solution that reacts with silver nitrate - HCl

Cl2 + 2H20 --> HCl + O2

8

Write a equation for the reaction between sodium hydroxide and ethanoic acid.

CH3COOH + NaOH --> CH3COONa + H2O

9

Suggest why the concentration of sodium hydroxide in a solution slowly
decreases when left open to air

NaOH reacts with carbon dioxide (in the air)

10

Reasoning for choosing a rate determining step

-Step which includes the SPECIES in the rate equation

11

CH3COCH2CH2CH3 CH3CH2COCH2CH3
Two ketone isomers.
Some students were asked to suggest methods to distinguish between isomers Q and R.
One student suggested testing the optical activity of the products formed when Q and
R were reacted separately with HCN.
Explain why this wouldn't work.

-Product Q is a racemic mixture
-Racemic mixture is optically inactive
-Product from R is inactive as no chiral centre

12

IUPAC name for glycerol

propane-1,2,3-triol

13

Give a use for the mixture of sodium salts that form in a reaction with glycerol

Soaps

14

Give a use for a mixture of methyl esters that form in a reaction with glycerol

biodiesel

15

Name a suitable reagent for the reduction dinitrobenzene, to a phenyldiamine (benzene with two NH2 groups)
write an equation for this reaction using [H] as the reducing agent

Sn/HCl
C6H4(NO2)2 + 12[H] --> C6H4(NH2)2 +4H20

16

Repeating unit of kevlar

-(N-H)-benzene-CONH-benzene-(C=O)-

17

Kevlar used as inner lining of bicycle tires.
Outer tyre made of polymerised alkenes
State the difference in biodegradability of the two.
Use your knowledge of the bonding in these polymer molecules to explain this
difference.

-Kevlar is biodegradable but polyalkenes not

-Kevlar has polar bonds/has peptide link/ is a poly amide

-Can be hydrolysed/attacked by nucleophiles/acids/bases/enzymes

-Polyalkenes not polar/non- polar bonds

18

Outline a three step synthesis of CH3CH2NH2 starting from methane. Your first step should involve the formation of CH3Cl.
In your answer, identify product of 2nd step and give reagents and conditions for each step
EQUATIONS & MECHANISMS NOT REQUIRED (6 MARKS)

Start with CH3CN

Step 1: React with Cl2 under UV light

Step 2: React with aqueous and alcoholic KCN (Allow UV)

Step 3: React with H2/Ni

19

Role of hydroxide ion in mechanism:

NOT 'Nucleophile'

Role is lone pair donor/base

20

Fermentation reaction with 2 essential conditions:

C6H12O6-----> C2H5OH + 2CO2
Conditions:
-No oxygen (anaerobic)
-(Enzymes from) yeast
-25-42 degrees

21

State the meaning of the term carbon-neutral

-No net/overall Carbon Dioxide emission to the atmosphere

22

Mean bond enthalpy: (2 marks)

-Enthalpy (energy required) needed in breaking a covalent bond
-Averaged over a range of compounds
(conditions: constant pressure)

23

Steps for identifying a molecule NMR large 8 mark question;

-State absorbtion peak (eg O-H 3230-3550)
-state peak numbers and infer (4 h1 peaks therefore 4 different hydrogen environments)
-Simplify integration splitting

24

Give two reasons why Tetramethylsilane is a suitable standard

- Inert
-All protons in same environment

25

Give an example of a solvent which is suitable for use in recording an nmr spectrum, Give a REASON

-CCl4
-"Proton Free" (means no hydrogen atoms)

26

What can the reaction of alcohols (eg butan-2-ol) with concentrated sulfuric acid give you?
and name the role of h2so4 in producing byproduct.

Can produce multiple alkenes, and a ketone as a byproduct. (Of the same alkyl eg butan-2-ol would produce multiple different butenes and butanone)
ROLE OF SULFURIC ACID IN KETONE PRODUCTION: OXIDISING AGENT

27

Role of sulfuric acid when it reacts with solid sodium chloride

Acid

28

Conditions for catalytic cracking:

-Slight pressure
-High temp

29

Icicle looking transmittance on nmr spectrum over O-H absorbtion area, is it a peak?

No, noticable peaks are large and wave looking

30

Is a singlular sharp peak above C=O a peak?

Yes. (If that is the only peak most likely an aldehyde)

31

Reaction where C3H6 is produced from CH3CH2CH2Br. Identify reagent and conditions:

NaOH and ethanol

32

Reasons for a molecule not showing stereoisomerism

-Not having a chiral centre
-Symmetrical

33

State in general terms what determines the distance travelled by a spot in TLC

-Balance between solubility in moving phase and retention by stationary phase