Question

At stp, which gaseous sample has the same number of molecules as 3.0 liter of N2(g)

Answer 1

The answer is: 3.0 L of CH4(g).

Vm = 22.4 L/mol; molar volume at STP (Standard Temperature and Pressure).

At STP one mole of gas occupies 22.4 liters of volume.

In this question all substances are gases, amount of substance depends on volume of the gas.

Same volume, same number of molecules.

So 3 liters of hydrogen gas (H₂) has the same number of molecules as 3 liters of methane gas (CH₄).

Answer 2

Answer:

Hydrogen gas has the same number of molecules as 3.0 liter of nitrogen gas.

Explanation:

Given volume of nitrogen gas at STP = 3 L

Moles of nitrogen gas = n

At STP, 1 mole of gas occupies 22.4 L of volume.

$n\times 22.4 L =3 L$

$n=\frac{3 L}{22.4 L}=0.1339 mol$

$1 mol = 6.022\times 10^{23}$ atoms/ molecules

Number of nitrogen gas molecules:

$0.1339\times 6.022\times 10^{23}=8.652\times 10^{22} molecules$

So, from the options, the gas with volume equal to the volume of nitrogen gas and will have moles equal to number of moles of nitrogen with which it will also have same number of molecules of gas.

Volume of fluorine gas = 6.0 l

Volume of hydrogen gas = 3.0 L

Volume of nitrogen gas = 4.5 L

Volume of chlorine gas = 4.5 L

Volume of hydrogen gas = Given volume o nitrogen gas = 3.0 L

Hydrogen gas has the same number of molecules as 3.0 liter of nitrogen gas.