Explanation:
A nucleophile is a species that is electron-rich and an electron donor.
An electrophile is an electron deficient species.

Explanation:
Oxidation involves the loss of electrons and an increase in oxidation state.

Explanation:
Lewis bases are electron pair donors and so, must have a lone (non-bonding) pair of electrons.

Explanation:
An acidic buffer solution contains a weak acid and the salt of its conjugate base.

Explanation:
Lewis acids are electron pair acceptors.
BF3 and AlCl3 both have incomplete octets and so can accept a pair of electrons.
Electrophiles, by definition, are electron-deficient species that accept pairs of electrons. Nucleophiles are electron-rich species that donate pairs of electrons (Lewis bases).

Explanation:
NaOH is a base so reacts with a hydrogen ion. HNO3, nitric acid, releases a hydrogen ion through the breaking (heterolysis) of the O-H bond.
This question is moderately difficult as the student must recognise that NaOH is a base and HNO3 an acid and correctly interpret a structural formula that may be unfamiliar.

Explanation:
C3H8 is a saturated alkane and C3H6 is an unsaturated alkene. The test of unsaturation using Br2(aq) can demonstrate the presence or absence of a carbon-carbon double bond.
In the presence of a double bond, Br2(aq) can add across the double bond in the alkene producing a dibromo-alkane, and a change of color from brown to colorless will be observed.
In the case of the absence of a double bond (saturated hydrocarbon), no color change would occur.

Explanation:
Weak acids produce strong conjugate bases. The salt when dissolved in solution would therefore be basic.

Explanation:
$)$ gains electrons and is reduced to $\mathrm{Zn}(\mathrm{s})$ at the cathode. $\mathrm{l})$ loses electrons and is oxidised to Cl2(g) at the anode

Explanation:
The student must identify the reagents and conditions for three reactions. Only information stated explicitly in the syllabus is needed and no interpretation of structural formulas is required. This question is therefore, categorized as “easy”.
Alkenes react with HCl in an addition reaction, alkanes react with halogens in the presence of UV light through free radical substitution, and halogenoalkanes react with NaOH in a nucleophilic substitution reaction.

Explanation:
Use the mnemomic CNAP; cathode negative, anode positive for the polarity in electrolytic cells.

Explanation:
By definition an acid is a proton donor. Weak acids only partially dissociate in aqueous solution leading to poor conductivity.

Explanation:
In electroplating, the anode is made of silver metal, which is oxidized to Ag^+ ions. The Ag^+ ions are then reduced at the cathode to Ag metal, resulting in a coating around this object.
Any impurities will sink to the bottom of the vessel.
In electrolytic cells, the anode is positive, and the cathode is negative. As a result, electrons travel from positive to negative.

Explanation:
The HPO4^− ion contains two negatively charged oxygen atoms which can bond to hydrogen ions, producing phosphoric acid (H3PO4).
The HPO4^− ion can therefore react with two H+ ions.
This question is moderately difficult as the student must recognise that H^+ ions bond to the negatively charged oxygen atoms, or that HPO4^− is derived from H3PO4.

Explanation:
The student must be sufficiently familiar with the reactions covered in the syllabus to realize that sodium hydroxide would not be useful for producing a diol from an alkene. Alternatively, the question could be answered by recalling the use of sodium hydroxide in the other three reactions. The question is categorized as easy as only limited knowledge of reactions in the literature is needed.
Reactions B and C are both acid-base reactions where NaOH deprotonates the organic species.
Reaction D is a nucleophilic substitution of a halogenoalkane with OH− as the nucleophile.
Reaction A would require first halogenation (with e.g. Br2) followed by nucleophilic substitution.

Explanation:
By definition, these are the standard conditions that must be recalled.

Explanation:
Spontaneous reactions occur in voltaic cells converting chemical energy to electrical energy, whereas, non-spontaneous reactions occur in electrolytic cells requiring electrical energy and converting this to chemical energy.
Electrolytic cells typically consist of one reaction vessel containing the aqueous of molten electrolyte. No salt bridge is therefore required.

Explanation:
Non-spontaneous reactions take place in electrolytic cells using an external power supply.
The positive electrode is the anode where oxidation takes place.
The aqueous metal ion (Mx^+) is reduced at the cathode to produce the solid metal.

Explanation:
Recall of the nitration intermediate covered in the syllabus. This is formed after the NO2^+ electrophile has been attacked by benzene’s pi electrons.

Explanation:
H2O is more readily oxidized than Cl^− and SO4^2−, however, when concentrated aqueous NaCl is used, chlorine is produced at the anode

Explanation:
$\mathrm{l}$ is a neutral salt, Na2CO3 is a basic salt, and NaOH is a strong base.