Chemistry: Topic-wise Test- 6 - NEET MCQ

Cl show different oxidation state as -1 to +7 due to vacant d orbital.

As oxygen is more electronegative than Cl.

Oxygen size is small hence its more electronegative and show -2 oxidation states.

2x + 7 (-2) = 0

x = +7

• Autoxidation is any oxidation that occurs in presence of oxygen.
• The term is usually used to describe the degradation of organic compounds in air (as a source of oxygen).
• Autoxidation produces hydroperoxides and cyclic organic peroxides.

When zinc is placed in copper nitrate solution the intensity of the blue colour is produced and copper iron is deposited on zinc.

• This is a Redox reaction between zinc and an aqueous solution of copper nitrate occurring in a beaker.

oxidation state of Ag in tollen’s reagent is +1.

In A Ni has +4 oxidation state.

KCl.MgCl₂.6H₂O is double salt

In A one and more different types of ligands are present.

Oxalate is a bidentate ligand.

Ligands are named 1st followed by the name of central metal ion.

Cis Platin (cis – [Pt(NH₃)₂(Cl)₂] is a anti cancer drug.

The correct answer is option D(None of the above)
The given compound is 4-Bromo-3methylheptanal

Alcohols have higher boiling points than aldehydes.

This is 1-phenyl propan-1-one.

The correct answer is option C
CH_3​CH₂​CONH₂​ (A)⟶ CH₃​ − CH₂ ​− NH₂​ (B)⟶ ​CH_3​ − CH₂ ​− OH
In the above sequence A & B respectively are Br₂​/KOH and HNO₂​
The first step is Hoffmann bromamide degradation reaction in which an amide (propanamide) is converted to an amine  (ethylamine) containing one carbon atom less. The reagent A is bromine in presence of KOH. In the second step, aliphatic primary amine (ethyl amine) reacts with nitrous acid (reagent B) to form aliphatic primary alcohol (ethyl alcohol).
 

Fe + HCl is preferred due to the following reasons:
- Scrap iron i.e Fe is cheap and commercially easily available
- FeCl₂ formed will get hydrolysed and release HCl, so, HCl which is required in the reaction will be produced by itself
- Hence only small amount of HCl is required to initiate the reaction.

−NO₂ group is reduced to –NH₂ using H₂/Pd.

Diphenhydramine​ is an antihistamine mainly used to treat allergies. It can also be used for insomnia, symptoms of the common cold, tremor in parkinsonism, and nausea. It is used by mouth, injection into a vein, injection into a muscle, or applied to the skin.

RNO₂ +Fe/HCl ->RNH₂

As the number of alkyl group increases, due to +I effect the basicity of amines increases.

p-amino azo benzene is obtained by treating diazonium chloride with aniline. The reactions are specifically acid catalyzed and involve pre‐equilibrium formation of amine and diazonium salt followed by rate‐limiting attack of the diazonium ion at a C‐atom (C‐coupling) to give the corresponding amino azo compounds.

The correct answer is option A

Hypophosphorous acid when treated with diazonium salts is reduced to arenes.
ArN₂Cl + H₃PO₂ + H₂O ⟶ ArH + N₂ + H₃PO₃ +HCl

The correct answer is Option A.
Aromatic Primary amine will form the most stable diazonium salt because it releases water when it reacts with nitronium ions. If aliphatic primary amine reacts with nitrosonium ion it Also releases water but in this case water reacts with alkyl diazonium salt and it forms alcohol while benzene diazonium salt does not react with water at this temperature.

Replacement of diazo group by other group is helpful in preparing compounds which are not/ cannot be produced by direct nucleophilic substitution reaction.This is because,to substitute in aromatic ring, the nucleophilic should leave the partial double bond, which is more energy required than in haloalkane.

As it is given that this reaction is in acidic medium, that means we have H+ on the reactant side so to balance Oxygen we have to add water on the product side instead of adding just Oxygen.

Oxidation half reaction for a reaction is that reaction which gives us the reactant and product formed after the oxidation of the reactant. In this case Fe⁺² oxidizes itself to Fe⁺³ and so the oxidation of Fe⁺² is oxidation half reaction. Option d correct.

The solutions in which the electrodes are immersed are called electrolytes. The chemical reaction that takes placein a galvanic cell is the redox reaction. One electrode acts as anode in whichoxidation takes place and the other acts as the cathode in which reductiontakes place.the half-cell occurs is called reduction half-cell and the reaction taking place in it is called reduction half-cell reaction. The electrode where oxidation occurs is called anode and the electrode where reduction occurs is termed cathode. Electrons flow from anode to cathode in the external circuit.

The standard potential of hydrogen electrode is assumed to be zero at all temperature.

The Standard hydrogen electrode (abbreviated SHE), is a redox electrode which forms the basis of the thermodynamic scale of oxidation-reduction potentials. Its absolute electrode potential is estimated to be 4.44 ± 0.02 V at 25 °C, but to form a basis for comparison with all other electrode reactions, hydrogen's standard electrode potential (E⁰) is declared to be zero volts at all temperatures.