Question

A closed bottle containing water (at ${30}^o$C) is carried in a spaceship and place on the surface of the moon. What will happen to the water when the bottle is opened?

• A. Nothing will happen to it
• B. Water will freeze
• C. Water will boil
• D. It will decompose into $H_2$ and $O_2$

Answer 1

The correct option is C Water will boil

In space, where there is no air, there is no air pressure. As air pressure drops, the temperature needed to boil water becomes lower. This is so because boiling point is the temperature at which vapour pressure of liquid is equal to the external pressure and in space external pressure is zero.