The density of phosphorus vapour at 310° C and 775 mm Hg is 2.64 g/l. Molecular formula of phosphorus is:

Question

The density of phosphorus vapour at 310° C and 775 mm Hg is 2.64 g/l. Molecular formula of phosphorus is: (A)  P2  (B)  P4  (C)  P3  (D)  P8

Tardigrade Admin · Accepted Answer

Vapour density of phosphorus at 310° C and 775 mm Hg is 2.64 g/l. i.e., P1=775 mm=(775/760)atm T1=310+273=583 K d=(w/V)=2.64 textg/l According to gas-equation: PV=nRT=(w/m)RT or m=(w/V)⋅ (RT/P) or m=(2.64× 0.0821× 583/775 text/760) Atomic weight of phosphorus is 31. Hence number of atoms bonded together to form one molecule will be =(124/31)=4. Hence, molecular formula of phosphorus =P4.

Q. The density of phosphorus vapour at $310^{\circ} C$ and 775 mm Hg is 2.64 g/l. Molecular formula of phosphorus is:

$P_{2}$

$P_{4}$

$P_{3}$

$P_{8}$

Q. The density of phosphorus vapour at 310∘C and 775 mm Hg is 2.64 g/l. Molecular formula of phosphorus is:

P2​

P4​

P3​

P8​

Q. The density of phosphorus vapour at $310^{\circ} C$ and 775 mm Hg is 2.64 g/l. Molecular formula of phosphorus is:

$P_{2}$

$P_{4}$

$P_{3}$

$P_{8}$