Vapor pressure -- How does water still boil at 100°C in an open pot?

Thread starter pisluca99
Start date Dec 2, 2022
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Boil Pressure Vapor Vapor pressure Water

In summary: The vapor pressure is not the same as the atmospheric pressure. Vapor pressure is the pressure of the vapor when it is in equilibrium with its liquid. This only happens when the container where the liquid is present is closed. Indeed, when the container is open, this liquid-vapour equilibrium is never reached, because the partial pressure of the vapor (at a given temperature) never reaches the vapor pressure.

Dec 5, 2022

russ_watters

Mentor

pisluca99 said:

But bubbles are made of vapor, and they are generated from the bottom of the container...

When boiling. Not when not boiling.

<h2>1. What is vapor pressure?</h2><p>Vapor pressure is the pressure exerted by the vapor of a substance in a closed system at equilibrium with its liquid or solid form.</p><h2>2. How does vapor pressure affect boiling point?</h2><p>Vapor pressure and boiling point are directly related. As vapor pressure increases, the boiling point of a substance decreases. This means that a substance with a higher vapor pressure will boil at a lower temperature.</p><h2>3. Why does water still boil at 100°C in an open pot?</h2><p>Water still boils at 100°C in an open pot because the atmospheric pressure is exerting a force on the surface of the water, preventing it from turning into vapor. This is why water boils at a lower temperature at higher altitudes, where the atmospheric pressure is lower.</p><h2>4. How does the temperature of the water affect its vapor pressure?</h2><p>The temperature of the water directly affects its vapor pressure. As the temperature increases, the vapor pressure also increases. This is because at higher temperatures, more molecules have enough energy to escape the liquid and become vapor.</p><h2>5. Can water boil at a temperature other than 100°C?</h2><p>Yes, water can boil at a temperature other than 100°C. As mentioned before, the boiling point of water is dependent on the atmospheric pressure. If the pressure is increased, the boiling point also increases, and if the pressure is decreased, the boiling point decreases. This is why water can boil at different temperatures in different environments.</p>

1. What is vapor pressure?

Vapor pressure is the pressure exerted by the vapor of a substance in a closed system at equilibrium with its liquid or solid form.

2. How does vapor pressure affect boiling point?

Vapor pressure and boiling point are directly related. As vapor pressure increases, the boiling point of a substance decreases. This means that a substance with a higher vapor pressure will boil at a lower temperature.

3. Why does water still boil at 100°C in an open pot?

Water still boils at 100°C in an open pot because the atmospheric pressure is exerting a force on the surface of the water, preventing it from turning into vapor. This is why water boils at a lower temperature at higher altitudes, where the atmospheric pressure is lower.

4. How does the temperature of the water affect its vapor pressure?

The temperature of the water directly affects its vapor pressure. As the temperature increases, the vapor pressure also increases. This is because at higher temperatures, more molecules have enough energy to escape the liquid and become vapor.

5. Can water boil at a temperature other than 100°C?

Yes, water can boil at a temperature other than 100°C. As mentioned before, the boiling point of water is dependent on the atmospheric pressure. If the pressure is increased, the boiling point also increases, and if the pressure is decreased, the boiling point decreases. This is why water can boil at different temperatures in different environments.