Chemical Reactions and Processes

Raney nickel, which is very finely divided nickel powder, is a catalyst for the addition of hydrogen across C=C and C≡C bonds.

Both aluminosilicates and alumina serve as catalysts in fluid catalytic cracking (FCC) units. Platinum is not typically used in cracking processes - it is more common in reforming reactions.

Hydrogen in hydrocracking removes heteroatoms (S, N, O) and saturates cracked products. Isomerisation is catalyzed by acid sites, not directly by hydrogen.

Ammonium hydroxide is a solution of ammonia in water. It can be denoted by the symbols NH₃(aq). Although the name ammonium hydroxide suggests a base with composition [NH⁴⁺][OH⁻], it is actually impossible to isolate samples of NH₄OH. These ions only comprise a tiny fraction of ammonia.

This is the correct option as this is not a property of a base. Bases react with non-metal oxides to form salt and water.

This option is correct because when calcium hydride or hydrolith are reduced in the presence of carbon dioxide, calcium oxilate is produced.

This is option is correct because it is a catalytic promoter. It acts as a promoter for iron catalyst in the manufacture of ammonia by Haber's process.

This option is correct as shape selective catalysis is catalysis by zeolite. The reaction taking place in zeolite depends on the size and shape of the reactant and product molecules as compared to those pores and cavities of zeolite, that is why it is called as shape selective catalysis.

Combustion produces both heat and light (option C). Combustion is an exothermic chemical reaction between a fuel and oxidant that releases energy in the form of heat and often light (as in flames). Options A and B are incomplete as combustion typically produces both, and option D is incorrect because heat and light are indeed produced.

Vanadium Pentoxide (V2O5) is used as a catalyst in the Contact process (option A). The Contact process produces sulfuric acid by oxidizing sulfur dioxide to sulfur trioxide, with V2O5 as the catalyst. The Haber process produces ammonia using iron catalysts, and the Solvay process produces sodium carbonate without V2O5.

Lead nitrate decomposes on heating (thermal decomposition) to form lead oxide, nitrogen dioxide, and oxygen. This is a chemical change as new substances are formed. Sodium chloride and silica are stable to heat, while platinum wire only undergoes physical change.

Copper reacts with dilute nitric acid to form nitrogen monoxide (NO), copper nitrate, and water. The NO is initially colorless but quickly oxidizes in air to brown NO2. With concentrated nitric acid, NO2 is produced directly.

It consists of several elements.

Pressing nitrogen tri-iodide triggers its explosive decomposition (chemical change). Mixing solid NaHCO3 with solid tartaric acid causes no reaction without water, so this is the only physical change. Phosphorus spontaneously ignites in oxygen (combustion, chemical change). Electrolysis of acidified water decomposes it into H2 and O2 gases (chemical change).