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

Explanation​:
In this nucleophilic substitution reaction, the hydroxide donates a lone pair to break the C-Br bond and form a new C-O bond. The C atom of compound B accepts the electron pair, so is an electrophile.
The compound is a secondary bromoalkane, as the C atom of the C-Br bond is attached to two C atoms.

Explanation:​
A secondary alcohol is a compound in which the carbon attached to the hydroxyl group is also attached to two other carbons.
Upon its oxidation, a removal of 2H atoms occurs and a ketone is formed.

A

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:​
Reducing agent is a substance that is oxidized.
Oxidation state of Zn increases from 0 to +2, whereas the oxidation state of N decreases from +5 to +4.
The oxidation state of H remains +1.
The oxidation state of O remains -2.

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

Explanation:​
The conjugate base of HCl is the compound produced when a hydrogen ion is removed. The conjugate base is therefore the chloride ion, Cl^−.
This question is hard as the student must link the names of chemicals to their formula and identify a conjugate base without the aid of an explicit reaction equation.

Explanation​:
More reactive metals are more likely to lose electrons (be oxidised) and so, Zn(s) will lose electrons to produce Zn^2+(aq) .
Cu^2+(aq)will gain electrons forming Cu(s) leading to a decrease in Cu^2+(aq) concentration and a paler blue colour of the solution.
Electrons flow from the anode(Zn) to the cathode (Cu).

Explanation:​
Students must compare ways of breaking bonds. They must recall that homolytic fissions form free radicals (species with unpaired electrons) as shared electrons split once the bond breaks.
In contrast, heterolytic fissions produce positively and negatively charged particles (ions) as both shared electrons go to just one of the atoms in the bond.

This question is categorized as hard. Students must recall the ways of breaking bonds, distinguish homolytic and heterolytic fission, and understand that free radicals have unpaired electrons.

Explanation:​
A tenfold decrease in [H+], leads to a $\mathrm{pH}$ increase of 1.

Explanation​:
By definition, the more readily an acid releases a proton, the less likely the conjugate base is to accept a proton.

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

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

Explanation​:
Step 1 is a free radical substitution, converting the alkane to a chloroalkane and producing HCl as a by-product.
Step 2 is a nucleophilic substitution, in which the C−Cl bond breaks and is replaced by a hydroxyl (C−OH) group; the products are an alcohol and sodium chloride.
Step 3 is an oxidation. To prevent the aldehyde from being oxidised further to a carboxylic acid, the product must be removed by distillation as it forms.

Explanation:
NaOH is a strong base and has a high pH,  NH3,​ is a weak base with a lower $\mathrm{pH}$ than NaOH. CH3COOH​ is a weak acid, $\mathrm{HCl}$ is a strong acid and so has the lowest pH.

Explanation:​
The HPO^4− ion contains two negatively charged oxygen atoms which can bond to hydrogen ions, producing phosphoric acid (H3PO^4​).
The HPO^4− 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 HPO^4− is derived from H3PO^4​.

Explanation:​

Hydrochloric acid produces chloride salts, nitric acid produces nitrate (NO3^−​) salts, sulphuric acid produces sulphate (SO4^2−​) salts, and ethanoic acid produces ethanoate (CH3​COO^−) salts.

Explanation:​

Acids react with carbonates to produce a salt, water, and carbon dioxide.

Explanation​:
Cathode site of reduction, anode site of oxidation, use CROA to remember this.
Reduction is the gain of electrons.

Explanation:​
Water accepts a hydrogen ion to produce H3O^+. This question is easy as the formation of H3O^+ is covered explicitly in the syllabus

Explanation​:
The positive ions (cations) move in the direction of the cathode as the positive Cu2+ ions are used up.
Zn being more reactive than copper, Zn(s) is the anode where oxidation occurs, and Cu(s) is the cathode where reduction of Cu2+(aq) occur

Explanation:​
$\mathrm{pH}$ = $-$.
For concentrations of H+ greater than 1 mol dm^−3, this would result in a negative $\mathrm{pH}$ value.

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.