Water’s boiling temperature is 100C or 212F, when you spill some on concrete or leave a cup of water outside, it disappears without it reaching 100C even if it is in the shade. The water from the ocean also evaporates, but it is not boiling. This happens with other liquids to such as isopropyl alcohol, or gasoline.
How does this happen?
In: Chemistry
All liquids have the ability to give off molecules in the gas phase: this is called the vapor. Boiling is a very specific event that occurs when the vapor pressure (the pressure of the vapor) equals the pressure of the air above the liquid.
Molecules can randomly exit the liquid phase and become gas. However, as long as the temperature is below the boiling point, those molecules will generally get pushed back into the liquid by the air pressure. As you increase the liquid’s temperature, those molecules get better and better at escaping, so they can “fight back” against the air pressure through their own pressure (vapor pressure). Once the temperature reaches the boiling point, their pressure is enough to counteract the air pressure, and the air pressure can no longer keep them in the liquid: they now have the strength to fight back and exit the liquid whenever they feel like it.
So when the vapor pressure (vapor molecules pushing on the air above) equals and then exceeds the air pressure (air pushing the vapor back down), the vapor is free to escape and the liquid starts to boil because there’s nothing keeping it in the liquid state anymore
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