how many molecules of CH4 gas are present in a 1.00 L flask of CH4 gas at STP?
How many moles are present? 1 mole will occupy 22.4 L and it will contain 6.022E23 molecules.
1 atm *1.00L= n * 0.0821(atm-L/ mol-K) * 273 k
n= 0.0446 mol
0.0446 mol * 6.02 * 10^23 (molecules/mol)=