A cylinder of 20 litres capacity contains a gas at 100
atmospheric pressure. How many flasks of 200 cm
capacity can be filled from it at 1 atmosphere pressure,
temperature remaining constant ? [Ans. 10,000 flasks]
Answers
Solution:
As per the given data,
- P₁ = 100 atm
- V₁ = 20 L
- P₂ = 1 atm
Step I: Find V₂
As per the ideal gas equation,
here,
- P = pressure
- V = volume
- n = moles
- R = universal gas constant
- T = temperature
All the terms on the R.H.S are constant.
⇒ PV = constant
From this, we can conclude that,
P ∝ 1 / V
Boyle's Law
This law states that the pressure of an ideal gas is inversely proportional to its volume at a constant temperature.
Hence,
⇒ P₁ V₁ = P₂ V₂
⇒ V₂ = P₁ x V₁ / P₂
⇒ V₂ = 100 x 20 / 1
⇒ V₂ = 2000 L
Volume of one flask = 200 cm³ = 200 x 10⁻³ L
Total no of flasks required to occupy a volume of 2000 L
= 2000 / 200 x 10⁻³
= 10,000
The total number of flasks is 10,000.
Question:
A cylinder of 20 litres capacity contains a gas at 100 atmospheric pressure. How many flasks of 200 cm³ capacity can be filled from it at 1 atmosphere pressure, temperature remaining constant?
Answer:
Given:
V1=20L=20000cm³
P1=100atm
V2=?
P2=1
According to Boyles' Law,
P1V1=P2V2
Solution:
100 × 20000 = 1 × V2
2000000 = V2
Also asked that,
how many flasks of 200 cm³ capacity can be filled from it at 1 atmospheric pressure and temperature remain constant.
Therefore,
According to Question:
2000000cm³ ÷ 200cm³
=10000 flasks Ans