Question

According to Avogadro's law how many molecules of any gas at STP are present in a volume of 22.41 L?

Answer 1

Moles( at STP)= PV/RT = 1X22.4/0.08X298 = ~ 1mol. Number of molecules at STP = moles at STP x Avogadro's number = 1 x 6.02x10^23 = 6.02x10^23 molecules.

Answer 2

Answer:

$6.018\times 10^{23} molecules$ of gas are present in 22.41 liter of gas at STP.

Explanation:

Using ideal gas equation:

PV = nRT

where,

P = Pressure of gas = 1 atm (STP)

V = Volume of gas = 22.41 L

n = number of moles of gas = ?

R = Gas constant = 0.0821 L.atm/mol.K

T = Temperature of gas = 273.15 K  (STP)

Putting values in above equation, we get:

$(1 atm)\times 22.41 L=n\times (0.0821L.atm/mol.K)\times 273.15 K\\\\n=0.9993 mole$

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

Number of molecules in 0.9993 moles of gas:

$=0.9993 mol\times 6.022\times 10^{23} molecules=6.018\times 10^{23} molecules$

$6.018\times 10^{23} molecules$ of gas are present in 22.41 liter of gas at STP.