A closed vessel contains pure water, in thermal equilibrium with its vapour at 25°C (Stage #1), as shown.The vessel in this stage is then kept inside an isothermal oven which is having an atmosphere of hot air maintained at 80°C. The vessel exchanges heat with the oven atmosphere and attains a new thermal equilibrium (Stage #2). If the Valve A is now opened inside the oven, what will happen immediately after opening the valve?

• A. Water vapour inside the vessel will come out of the Valve A
• B. Hot air will go inside the vessel through Valve A
• C. Nothing will happen – the vessel will continue to remain in equilibrium
• D. All the vapour inside the vessel will immediately condense