Questions & Worked Solutions For Chemistry WCH15 May/June 2020
IAL Chemistry WCH15 May/June 2020 Questions - Complete Paper (pdf)
- The enthalpy change of hydrogenation of cyclohexene is −120kJ mol−1.
- Which orbitals overlap to form the ring of delocalised electrons in benzene and
what type of bond is formed?
- Which reagent and catalyst will convert benzene into phenylethanone?
- Chlorine reacts with methylbenzene in the presence of ultraviolet light.
Which of these is a product of this reaction?
- How many isomers containing a benzene ring are there with the molecular formula
- Phenol reacts with ethanoyl chloride to form phenyl ethanoate.
- A hydrocarbon contains 91.3% by mass of carbon.
Which of these could be the molecular formula of this compound?
- What is an organic product of the reaction between ethylamine and chloroethane?
- Which pair of monomers can form this polymer?
- Part of the structure of a protein is shown
- Which organic compound reacts with a Grignard reagent to give a product that forms
a secondary alcohol on hydrolysis?
- A compound with the formula C6H14 gives a 13C NMR spectrum with four peaks.
Which compound gives this spectrum?
- Cuminone is used as a flavouring.
- Which species contains an element with the same oxidation number as bromine
- Which is a redox reaction?
- The electronic configuration of the atoms of an element is 1s22s22p6
What is the maximum oxidation number shown in compounds of this element?
- Which of the following species will not act as a ligand in the formation of a
- What is the coordination number of the nickel(II) ion and the overall charge, m,
of this complex?
- In acidic conditions, manganate(VII) ions are reduced to manganese(II) ions, Mn2+.
In neutral conditions, manganate(VII) ions are reduced to manganese(IV) oxide, MnO2.
of a solution of manganate(VII) ions were needed to oxidise 25.0cm3
solution of iron(II) ions to iron(III) ions in acidic conditions.
The same solution of manganate(VII) ions is used to oxidise 25.0cm3
of the same
solution of iron(II) ions in neutral conditions.
By considering the oxidation number changes involved, it may be shown that the
volume of the manganate(VII) solution required, in neutral conditions, is
- A solution contains 19.6g dm-3 of chromium(III) sulfate, Cr2(SO4)3.
What is the concentration, in mol dm-3, of sulfate ions in this solution?
- This question is about electrochemical cells.
(a) The half-equation for an iron(III)/iron(II) half-cell is
(b) The cell diagram for an electrochemical cell is
(c) The standard electrode potential, E, for the chromium(III)/ chromium half-cell is −0.74 V
- This question is about aromatic amines and amino acids.
(a) A synthesis of phenylamine is shown.
(b) Phenylamine is a base.
(i) Explain why phenylamine is a weaker base than ammonia.
(ii) State what is seen when a few drops of an aqueous solution of phenylamine
are added to an aqueous solution containing Cu2+ ions
(c) Azo violet is used as a dye and an indicator.
A synthesis of azo violet from 1-amino-4-nitrobenzene is shown
(d) Phenylalanine is an amino acid that exists as optical isomers.
The structure of one of the optical isomers is shown.
Complete the diagram to show the other optical isomer of phenylalanine
- This question is about some organic compounds.
(a) A mixture of methane and ethane with a total volume of 25.0cm3
of oxygen for complete combustion.
All gas volumes were measured at the same temperature and pressure.
Determine the percentage, by volume, of methane in the mixture.
(b) Devise a reaction scheme to convert butan-2-ol into 1-amino-2-methylbutan-2-ol
in three steps
- This question is about transition metals and their compounds.
(a) Three reactions were carried out on a solution containing [Fe(H2O)6]3+ ions
- The lanthanides form a series in the Periodic Table comprising the elements from lanthanum,
La (Z = 57) to lutetium, Lu (Z = 71). They have important uses as elements and compounds, for
example, in the screens, circuits and speakers of smartphones. These elements have some similar
properties to d-block elements
Try the free Mathway calculator and
problem solver below to practice various math topics. Try the given examples, or type in your own
problem and check your answer with the step-by-step explanations.
We welcome your feedback, comments and questions about this site or page. Please submit your feedback or enquiries via our Feedback page.