MHT CET202613 April 2026Morning ShiftChemistrySome Basic Concepts of ChemistryActual
Which of the following contains maximum number of molecules?
Options
- A0.4 g H ₂ gas
- B3.2 g of O ₂ gas
- C16.8 dm ^3 of H ₂ gas at STP
- D11.2 dm ^3 of O ₂ gas at STP
Correct answer
C. 16.8 dm ^3 of H ₂ gas at STP
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