Suppose 30.4 mol of krypton is in a rigid box of volume 46 cm3 and is initially at temperature 438.28°C. The gas then undergoes isobaric heating to a temperature of 824°C. (a) What is the final volume of the gas? (b) It is then isothermally compressed to a volume 24.3cm3; what is its final pressure? cm (a) Answer part (a) Answer part (b) (b) Pa

Initial volume v₁ = 46 x 10⁻⁶ m³

Initial temperature T₁ = 438.28 + 273 = 711.28 K

Initial pressure P₁ = nRT₁ / v₁

= 30.4 x8.3 x 711.28 / (46 x 10⁻⁶)

= 3901.5 x 10⁶ Pa

Final temperature T₂ = 824 + 273 = 1097 K

Final volume V₂ = ?

For isobaric process

v₁ / T₁ = V₂ / T₂

V₂ = V₁ X T₂ / T₁

= 46 X 10⁻⁶ X 1097 / 711.28

= 70.94 X 10⁻⁶ m³ = 70.94 cm³

b) For isothermal change

P₁ V₁ = P₂V₂

P₂ = P₁V₁ / V₂

= 3901.5 X 10⁶ X 46 / 24.3

7385.55 X 10⁶ Pa.