Question

At stp, a 12.0 liter sample of CH4 has the same total number of molecules as

Answer 1

2 the answer is 12.0 L of CO2(g) at STP

Answer 2

Option 2: 12.0 L of
`CO_(2) (g)` at STP.

The standard pressure and temperature values are 1 atm and 273.15 K.

Using the ideal gas equation, number of moles of gas can be calculated which is as follows:

PV=nRT...... (1)

Here, P is pressure, V is volume, n is number of moles, R is gas constant and T is temperature.

Also, in 1 mole of any gas there are
`6.023* 10^(23)` molecules of the gas. This is known as Avogadro's number and denoted by symbol
`N_(A)`

Thus,

`N=n* N_(A)`

Equation (1) can be rewritten as follows:

`PV=(N)/(N_(A))RT`

On rearranging,

`N=(P* V* N_(A))/(R* T)`

Here, all the other terms are constant except volume, thus, gas with volume equal to the volume of
`CH_(4)` will have same number of molecules.

Volume of
`CH_(4)` gas and
`CO_(2)`gas is same thus,
`CH_(4)` will have same total number of molecules as
`CO_(2)` gas.