Question

Which sample at STP has the same number of molecules as 5 liters of NO2(g) at STP?

(1) 5 grams of H2(g)
(2) 5 liters of CH4(g)
(3) 5 moles of O2(g)
(4) 5 × 1023 molecules of CO2(g)

Answer 1

I believe the answer is (2) 5 liters of CH4(g). Hope this helped! :)

Answer 2

(2) is the only correct answer. (1) 5 grams of H2 is 2.5 mols of this gas, which would result at STP 22.4 * 2.5 Liters (according to Avogadro's law). 5 moles of O2 would result in 5 * 22.4 Liters, and (4) 5 * 10^23 molecules of CO2 (which is what I assume you meant) would be 5 mols, which would result in 5* 22.4 Liters.


(2) is your answer