Question

a diatomic gas occupies 0.8 litre per gram at ntp how many atoms are contained in 0.8 litre at ntp​

Answer 1

The number of atoms of 3.998 × 10²² atoms.

Step-by-step explanation:

The given gas is in normal temperature and pressure (NTP).

The ideal gas equation is:

PV = nRT

Where,

P = Pressure = 1 atm

V = Volume = 0.8 L (given)

n = Number of moles = ?

R = Gas constant = 0.08205 L.atm/mol.K

T = Temperature = 293.15 K

On substituting the values, we get,

1 × 0.8 = n × 0.08205 × 293.15

n = (1 × 0.8)/(0.08205 × 293.15)

∴ n = 0.0332 moles

Now,

Number of molecules is:

⇒ n × Avogadro's number

⇒ 0.0332 × 6.022 × 10²³

∴ 1.999 × 10²² molecules

From question, the gas is a diatomic gas.

⇒ 1.999 × 10²² × 2

∴ 3.998 × 10²² atoms