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(i) Ethylbenzene

In the presence of nascent oxygen i.e. [O] along with KMnO₄/ KOH (it is a very strong oxidizing agent which oxidizes the whole alkyl group to carboxylic salt) followed by hydrolysis leads to the formation of benzoic acid. Carbon dioxide and water are formed as byproducts.

(ii) Acetophenone

The oxidation with alcoholic KMNO₄ followed by hydrolysis leads to the formation of benzoic acid. The reaction is given below:

(iii) Bromobenzene

Bromobenzene is first reacted with magnesium in presence of dry ether to give an intermediate which on reaction with solid carbon dioxide followed by hydrolysis leads to the formation of benzoic acid.

(iv) Phenylethene (Styrene)

Here the oxidation of styrene with alcoholic KMNO₄ is followed by hydrolysis leads to the formation of benzoic acid.

(i) Ph CH₂ COOH The compound contains carboxylic acid as the functional group and Ph means a phenyl group. The longest chain contains 3 carbon atom with phenyl group of carbon 3 so the IUPAC name of the compound is 3-phenylpropanoic

(ii) (CH₃ ) ₂ C=CHCOOH

The longest chain contains 4 carbon atom with a methyl group as a substituent and a carboxylic acid as a functional group. The no. Of the chain starts from the carbon atom of the –COOH group with double bond on carbon 2 so the IUPAC name of the compound is 3-Methylbut-2-enoic acid.

(iii) The longest chain has 5 carbon atom (all are saturated) which are cyclic with the carboxylic group attached and a methyl group as a substituent. The no. Of the chain starts from the carbon atom of the – COOH group so the IUPAC name of the compound is 2-Methylcyclopentane carboxylic acid.

(iv) The longest chain is derivative of benzene with the carboxylic group attached and 3 nitro groups. The number of the chain starts from the carbon atom of the –COOH group so the IUPAC name of the compound is 2,4,6-Trinitrobenzoic acid.

(i) Ethanal, Propanal, Propanone, Butanone

The +I effect increases in the order as:

Ethanal

Therefore, the electron density of the carbonyl carbon increases as the +I effect due to the alkyl group increases. As a result, the chances of attack by a nucleophile (which are rich in electrons and carry a negative charge, not necessarily usually have a lone pair of an electrons) decrease because the carbonyl carbon has electron density on it. Hence, the increasing order of the reactivity of the given compounds in nucleophilic addition reaction is:

Ethanal > Propanal> Propanone > Butanone.

(ii) Benzaldehyde, p-Tolualdehyde, p-Nitrobenzaldehyde, Acetophenone:

The +I effect is more in ketone than in aldehyde because in ketone, there are 2 alkyl groups contributing in the +I effect whereas in aldehydes, there is only one alkyl group. Hence, acetophenone (being a ketone group attached to it) is the least reactive in nucleophilic addition reactions.

Among aldehydes, the +I effect is the highest in p-tolualdehyde because of the presence of the electron- donating –CH₃ group (which increase the electron density on the carbonyl carbon via resonance through the benzene ring) and the lowest in p-nitrobenzaldehyde because of the presence of the electron- withdrawing –NO₂ group (which decreases the electron density on the carbonyl carbon via resonance through the benzene ring). Hence, the increasing order of the reactivity of the given compounds is:

Acetophenone<p-tolualdehydep-Nitrobenzaldehyde

The molecular masses of the given compounds are in the range of 44-66 g/mol. The second molecule, CH₃CH₂OH contains OH alcoholic group due to which it undergoes extensive H bonding with each other molecules, leading to the association of the molecules. Therefore, it has the highest boiling point. In the molecule CH₃CHO, there is strong intermolecular dipole-dipole attraction due to presence of - CHO aldehydic group ( as H will have partial positive charge and oxygen will have partial negative charge, so there will attraction between molecules), which is weak in case of CH₃OCH₃ as both CH₃ groups have +I effect which results in decrease in electron affinity for the oxygen attached to it ( with no partially positive H atom). And in CH₃CH₂CH_3, there are only weak van there Waals forces of attraction. So the compounds in increasing order of their boiling point are:

CH₃CH₂CH₃< CH₃OCH₃< CH₃CHO< CH₃CH₂OH.

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But now, human scoring has been additionally incorporated for a double verification and fairer scoring. 

The human scoring is done in two ways for the lived test responses of the PTE Academic Test:

1. For the anomalies: This is the area where the unusual answers cannot be scored by automation and hence, human expertise is equired. 
2. Task Specific: The "Describe Image" and the "Retell Recture" tasks of the PTE test are also be scored by the human experts now.