James Chadwick bombarded beryllium with alpha particles and discovered: MCQ with Answer and Explanation

Explanation:
Sulphuric acid is a key reagent in many processes: to produce HCl from NaCl, HNO₃ from nitre, fertilizers (superphosphate), and in petroleum refining, pickling, etc. It is also used as a dehydrating agent and catalyst. Ammonia is made by Haber process without H₂SO₄. NaOH is made by electrolysis of brine. H₂SO₄ is known as 'king of chemicals'.

Explanation:
UV irradiation uses ultraviolet light to disrupt the DNA of microorganisms, rendering them unable to reproduce and cause disease. It is a physical disinfection method, leaving no chemical residue. Chlorination uses chlorine, ozonation uses ozone, boiling uses heat.

Explanation:
In displacement reactions, a more reactive element displaces a less reactive one from its compound. Here, iron (more reactive than copper) displaces copper from copper sulfate. A is combination; B is decomposition; D is neutralization (double displacement).