MHT CET Chemistry Question (2026) — Solution

Step-by-step solution

The number of molecules is directly proportional to the number of moles. Number of moles of H _2 in 0.4 g = 0.4 2 = 0.2 mol Number of moles of O _2 in 3.2 g = 3.2 32 = 0.1 mol Number of moles of H _2 in 16.8 dm ^3 at STP = 16.8 22.4 = 0.75 mol Number of moles of O _2 in 11.2 dm ^3 at STP = 11.2 22.4 = 0.5 mol Since 0.75 mol is the maximum among the given options, 16.8 dm ^3 of H _2 gas at STP contains the maximum number of molecules. Answer: 16.8 dm ^3 of H _2 gas at STP