Question

In a certain region of space there are only 5 molecules per cm³ on average. The temperature is 3 K. The average pressure of this very dilute gas is ______ × 10^-21 atoms. 

पर्याय

• 1.06

• 1.06

• 2.04

• 0.05

Answer 1

In a certain region of space there are only 5 molecules per cm³ on average. The temperature is 3 K. The average pressure of this very dilute gas is 2.04 × 10^-21 atoms.

Explanation:

PV = nRT

P = `w/("V" xx "M")`RT

Here `w/("V" xx "n")` = 5 molecular/cm³

= 5 × 10³ L

or R = 0.0821 L-atom/K-mole

= 0.0821 × 10³ 

∴ P = `(5 xx 10^3 xx 0.0821 xx 3)/(6.02 xx 10^23)`

= 2.04 × 10^-21 atm