Which gas sample at stp has the same number
of molecules as a 2.0-liter sample of cl2(g) at
stp?
(1) 1.0 l of nh3(g) (3) 3.0 l of co2(g)
(2) 2.0 l of ch4(g) (4) 4.0 l of no(g)

STP signifies standard temperature and pressure. This conditions are at 1 atmospheric pressure and 0 degrees Celsius. It has been said that at these conditions, one mole of a gas molecule is equivalent to 22.4 liters of volume. Therefore, the correct answer is the second option which is 2 L of CH4.

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.