Evaporation and Boiling
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Factors affecting evaporation | Interactive Assessment Worksheets
© by Alan & Hui Meng
When the water temperature reaches 100°C, bubbles of water vapour form (throughout the water) and rise to the surface of the water and break. In other words, water starts to boil and changes into water vapour. The temperature 100°C is called the boiling point of water.

When the hot water vapour (steam) meets the cold air above the boiling water, it condenses into tiny water droplets to form 'white clouds'.