boiling

phase change

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Last updated

June 22, 2026

Quick Summary

Boiling is a phase change where a liquid transforms into a gas. This occurs when the liquid's vapor pressure equals the surrounding atmospheric pressure. At sea level, water boils at 100°C (212°F), but this temperature decreases at higher altitudes due to lower atmospheric pressure. Boiling involves the formation of vapor bubbles within the liquid. This process requires heat, and the heat of vaporization is a measure of the energy needed to overcome cohesive forces between molecules. Evaporation is a similar process but occurs below the boiling point.1234

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steam
…until the water reaches its boiling point; at this stage, represented by B and B′, the water is said to be in the saturated liquid state. If more heat is added, boiling begins: the liquid starts to vaporize (turn into steam), forcing the piston upward more rapidly than before, as…
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…until the water reaches its boiling point; at this stage, represented by B and B′, the water is said to be in the saturated liquid state. If more heat is added, boiling begins: the liquid starts to vaporize (turn into steam), forcing the piston upward more rapidly than before, as…
Read More

tin processing
Refining
One fire-refining method is called boiling. In this, impure tin from the smelter, or tin from the liquation furnace (see below), is heated in vessels or kettles that are agitated by compressed air. The effect is to oxidize the impurities, which rise to the surface and form a dross.
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One fire-refining method is called boiling. In this, impure tin from the smelter, or tin from the liquation furnace (see below), is heated in vessels or kettles that are agitated by compressed air. The effect is to oxidize the impurities, which rise to the surface and form a dross.
Read More

ultrasonics
Applications in research
When water is boiled, bubbles form at the bottom of the container, rise in the water, and then collapse, leading to the sound of the boiling water. The boiling process and the resulting sounds have intrigued people since they were first observed, and they were the object of…
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When water is boiled, bubbles form at the bottom of the container, rise in the water, and then collapse, leading to the sound of the boiling water. The boiling process and the resulting sounds have intrigued people since they were first observed, and they were the object of…
Read More