Question

one gram molecule of oxygen is heated at constant pressure from 0°c.What amount of heat should be imparted to the gas to double it's volume? given Cp =0.218cal g-1 0c-1.​

Answer 1

Given info : one gram molecule of oxygen is heated at constant pressure from 0° C.

To find : what amount of heat should be imparted to the had to double its volume ?

solution : one gram molecule means one mole.

so no of moles of oxygen gas , n = 1

work done , W = $\int\limits^{2V}_{V}{p}\,dV$ = PV = nRT₀ = 1 × R T₀ = RT₀

internal energy change, ∆U = $\int\limits^{2V}_{V}C_vdT$

= $\int\limits^{2V}_V{\frac{R}{\gamma-1}}\,dT$

we know, pdV = nRdT

so, $\int\limits^{2V}_V{\frac{P}{\gamma-1}}\,dV$

= $\frac{pV}{\gamma-1}=\frac{RT_0}{\gamma-1}$

now from 1st law of thermodynamics,

Q = W + ∆U

⇒Q = RT₀ + RT₀/(γ - 1)

for oxygen (diatomic molecule),

γ = 1.4

= 25/3 × 273 + 25/3 × 273/(1.4 - 1) J

= 2275 + 2275/0.4

= 2275 + 5687.5

= 7962.5 J

Therefore heat required to the gas to double its volume is 7962.5 J

Answer 2

Answer:

★one gram molecule of oxygen is heated at constant pressure from 0°c.What amount of heat should be imparted to the gas to double it's volume? given Cp =0.218cal g-1 0c-1.