Chemical Reactions and Equations

Metals react with oxygen to form basic oxides because they are electropositive elements that readily lose electrons. This is a key chemical property distinguishing metals from non-metals, which typically form acidic or neutral oxides. Option A is incorrect because metals tend to lose electrons (not gain). Option B is wrong because metals are reducing agents (not oxidizing agents). Option D is false because metals are electropositive (not electronegative).

 C is KOH and D is K₂O_2. These reactions take place in low temp. and high temp. respectively.

This option is correct because while the formula for equilibrium constant it is generalized as K = [products]/[reactants] ………………..where the concentration of pure reactants and products is taken to be unity.In the given reaction the concentration of reactant Zn(s) and product Cu(s) is to be taken unity and hence we will get the correct answer as K = [Zn²⁺]/[Cu²⁺]

This option is correct and can be explained as follows: For the give n reaction the equilibrium constant is given byK = [Ba²⁺][SO₄^2-]……………………….or we can say that [Ba²⁺] and [SO₄^2-] are having inversely proportional relationship whose graph is given by a rectangular hyperbola.

Hundsdiecker reaction and Sandmeyer reaction both proceed via free radical formation as an intermediate. Both Dieckmann condensation reaction and Claisen condensation reaction proceed via the formation of carbanions as an intermediate. Hence, 1 and 2 both the reactions proceed via free radical formation as an intermediate.

The oxidation of aromatic methyl groups to aldehydes with cromyl chloride (CrO₂Cl₂) is known as Etard reaction. The reaction of triphenylphosphine and tetrahalomethanes (CCl₄, CBr₄) with alcohols is a ready method to convert an alcohol to the corresponding alkyl halide under mild conditions in high yields. This reaction is known as Appel reaction.

In the heterolytic fission of a C-X bond in an organic molecule, if X is more electronegative than carbon atom, the former takes away the bonding electron pair and becomes negatively charged and results in the formation of positively charged species which is called carbocation. Many reactions are involved in the formation of carbocation as reactive intermediate like Friedal craft reaction, Baeyer-Villiger oxidation, Wagner-Meerwein rearrangement etc. Curtius rearrangement involves in the formation of nitrene with two unshared pair of electrons as a reactive intermediate.

A reaction intermediate is a molecular entity that is formed from the reactants and reagents to give products of a chemical reaction. Carbenes are highly reactive species having a very short life time (<1 sec) with two unshared electrons. The reactions involved in the formation of carbenes are Carbylamines reaction, Reimer-Tiemann reaction, Wolff rearrangement etc. In Lossen rearrangement, the reactive intermediate is a nitrene with two unshared pair of electrons.

This option is correct because in styrene, carbon atom attached to phenyl group is designated as α-carbon, while that carrying Cl-atom is designated as β-carbon.

When ammonia reacts with excess of chlorine,  nitrogen tri chloride (NCl₃₎ and hydrogen chloride(HCl) is formed.

When ammonia is oxidised in the presence of a catalyst pt then nitric oxide (NO) and water vapour is formed.

The required reaction is S + O₂→ SO₂ + Cl₂ (water) → SO₄^2– + BaCl₂→BaSO₄ +2Cl^–. Moles of sulphur = (8 / 32) = (1 / 4),  moles of SO2. Therefore, moles of BaSO₄ precipitated = 0.25. (applying principle of atom conservation). Hence, this is a correct option.

PdCl₂ is used as a ctatlyst in the conversion of ethene to ethanal in Wacker process. In Deacon process, CuCl₂ is used as a catalyst for the preparation of chlorine from HCl. Fe is used as a catalyst in Haber process for the formation of ammonia. A mixture of TiCl₄ and triethyl aluminium (Zeigler-Natta catalyst) is used for converting SO₂ to SO₃ in Contact process.

NADP+ is reduced to NADPH by accepting a hydrogen atom (which consists of a proton, H+, and an electron, e-). The reaction is: NADP+ + H+ + 2e- → NADPH. This occurs during the light-dependent reactions of photosynthesis. Oxygen, carbon, and nitrogen are not involved in this specific reduction reaction.

NADP+ gains a hydrogen ion (H+) and two electrons to become NADPH, the reduced form that carries energy to the Calvin cycle. This reduction occurs during the light-dependent reactions of photosynthesis when water molecules are split.