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O2.2 A CLOSER LOOK AT BOILING POINT (2)
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We do have water in both the liquid and gas states at 100ºC:

When water boils, the temperature inside the bubbles must be the same as the temperature of the surrounding liquid water - otherwise they would cool down, the gas water would condense and the bubbles would disappear.


The water is being heated all of the time as it boils:
Like melting, it takes energy for this change of state too. The water has to be at its boiling point and supplied with energy in order to change from the liquid to the gas state.

It takes 2,261 Joules to change 1g of water at 100°C from the liquid to the gas state (under normal air pressure).

 

 
not applicable
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o1: change of state
o2: boiling point


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