AIIMS 2015 Chemistry Question Paper for free online practice with solutions

When a substance ‘A’ reacts with water, it produces a combustible gas ‘B’and a solution of substance ‘C’ in water, while another substance ‘D’ reacts with solution of ‘C’ to produce the same gas B on warming while ‘D’ can produce gas ‘B’ on reaction with dilute H2SO4 at room temperature. ‘A’imparts a deep golden yellow colour to a smokeless flame on Bunsen burner.Identify ‘A’, ‘B’, ‘C’ and ‘D’ respectively are