At stp, a 12.0 liter sample of ch4(g) has the same total number of molecules as

There are four choices to choose from in regards with this problem and fortunately I know the answer to the said question:

Listed below are the choices:

a.) 6.0 L of H2(g) at STP
b.) 12.0 L of CO2(g) at STP
c.) 18.0 L of HCI(g) at STP
d.) 24.0 L of O2(g) at STP

The correct answer is b. 12.0 L of CO2 (g) at STP

Note:

STP or (Standard Temperature and Pressure) - most commonly used when performing calculations on gases (e.g. gas density)

The answer is c. 320 g