Question
Question: A \(1\) liter of an ideal gas at \({27^ \circ }C\) is heated at constant pressure to \({297^ \circ }...
A 1 liter of an ideal gas at 27∘C is heated at constant pressure to 297∘C , Its final volume will be:
(A) 11 litres
(B) 1.1 litres
(C) 3.4 litres
(D) 1.9 litres
Solution
From the constant pressure ideal gas equation, substitute the known values of the volume and the temperature to obtain the final volume of the ideal gas. The volume must be substituted in cubic centimeters and the temperature must be substituted in kelvin.
Useful formula:
The equation of the ideal gas at the constant pressure is given by
V2V1=T2T1
Where V1 is the initial volume of the ideal gas, V2 is the final volume of the ideal gas, T1 is the initial temperature of the ideal gas and T2 is the final temperature of the ideal gas.
Complete step by step solution:
It is given that the
Initial volume of the ideal gas, V1=1l=1000cc
Initial temperature of the ideal gas, T1=27∘C=300K
Final temperature of the ideal gas, T2=297∘C=570K
By using the equation of the ideal gas at the constant pressure, we get
V2V1=T2T1
Substituting the initial and the final temperature and the initial volume of the ideal gas to obtain the final volume.
V21000=570300
By grouping the known terms in one side and the unknown term in one side of the equation, we get
V2=3001000×570
BY performing various arithmetic operations, we get
V2=1900cc
By converting the cubic centimeter into the litre, we get
V2=10001900=1.9l
Hence the final volume of the ideal gas is obtained as 1.9 litre.
Thus the option (D) is correct.
Note: The ideal gas equation is PV=mRT , the constant pressure equation is formed from it. For converting the litre into the cubic centimeter, multiply the volume with the thousand and for converting the Celsius into the Kelvin, add the temperature with the number 273 .