Question

Total number of moles of oxygen atoms in 3 litres of O3 (g) at 27* C and 8.21 atm are?

Answer 1

Molar gas volume at STP = 22.4 litres

We need to convert this volume to the volume the gas would occupy at STP

p1 = 8.21 atm                                  p2 = 1 atm

v1 = 3 litres                                      v2 = ?

t1 = 27 + 273 = 300 k                       t2 = 273K

p1v1/t1 = p2v2/t2

(8.21x3)/300 = (1xv2)/273

From which

v2 = 22.4133 litres

Number of moles of O3 = 22.4133/22.4 = 1 mole


Each O3 molecule has 3 atoms of O

Number of moles of oxygen atoms =  3 x 1

                                         = 3

Answer 2

Answer:

3 moles

Explanation:

PV=nRT

So, PV/RT =n

Substituiting the values as

0.821×3/0.0821×300......................(27°C=300 K)

n=1 mole= NA molecules

Molecules              Atoms

1                                 3

NA                            3 NA atoms

Moles= No of entities/NA

Moles of O atoms= 3NA/NA

That is 3 moles