MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

The thermal decomposition of acetaldehyde is a well-known example of a reaction with a fractional order. The reaction is: CH _3 CHO _ (g) CH _ 4(g) + CO _ (g) The experimentally determined rate law for this reaction is: Rate = k[ CH _3 CHO ]^ 1.5 Thus, the overall order of the reaction is 1.5. For the other reactions: H _ 2(g) + I _ 2(g) 2 HI _ (g) follows second-order kinetics. 2 H _2 O _ 2(g) 2 H _2 O _ ( ) + O _ 2(g) follows first-order kinetics. 2 NO _ (g) + 2 H _ 2(g) N _ 2(g) + 2 H _2 O _ ( ) follows third-order kinetics. Answer: CH _3 CHO _ (g) CH _ 4(g) + CO _ (g)