What Are the Freezing, Melting, and Boiling Points of Solids, Liquids, and Gases?

Definition of Boiling Point

The temperature at which a liquid boils and turns into a gas is called the boiling point. The boiling point temperature will be lower if the atmospheric pressure is decreased. For example, the boiling point of pure water at standard atmospheric pressure (or sea level) is 100°C (212°F), while at 10,000 feet (3,048m), it is 90.39° C (194.7°F). This decrease will affect the time it takes to cook anything in water to the extent that any food that requires five minutes to prepare at sea level will take around 20 minutes at 3km (10,000 feet). In theory, you could also calculate your altitude by recording the temperature water boils at.

Solvent-based liquids will generally have a lower boiling point than water. In other words they will require less heat to turn them into vapour. Liquids with a much lower boiling point than water are generally classed as flammable.

Definition of Freezing Point

The temperature at which a liquid becomes a solid is the freezing point. The freezing point temperature will be higher if the pressure is increased. This may not be by a noticeable amount due to the volume change upon melting being much smaller than the volume change (expansion) when boiling. For example the freezing point of pure water at standard atmospheric pressure (or zero feet) is 0°C (32°F) while at 11km (6 miles) above sea level it would only be 0.001°C higher.

The only known liquid that does not freeze, even at absolute zero, is liquid helium unless it is under pressure.

Definition of Melting Point

The temperature that a solid substance becomes a liquid. Some solids do not have a liquid state and will change directly from a solid to a gaseous state. This is called sublimation, e.g. Carbon Dioxide (dry ice).

Melting Point/Freezing Point

The terms melting point or freezing point are often interchanged depending on whether a substance is being heated or cooled. For liquids it is known as the freezing point and for solids it is called the melting point. The melting point of a solid and the freezing point of the liquid are normally the same.

Table of Boiling and Melting/Freezing Points at Sea Level (Standard Atmospheric Pressure). The information is provided in centigrade (Celsius).

A to C

E to M

N to P

R to Z

Resources

More detailed information can be found from the following (small) selection of the many excellent publications and websites covering these subjects.

Recommended

Emily Dickinson’s "So has a Daisy vanished"

Barchi. Biman: Water in Biological and Chemical Processes

bismarkschools.org

calacademy.org (California Academy of Sciences)

Carslaw, HS: Conduction of Heat in Solids

chestofbooks.com

Collieu, AM & Powney DJ: Mechanical and Thermal Properties of Materia;s

Dann, Sandra E: Reactions and Characterization of Solids

Das, Shankar P: Statistical Physics of Liquids at Freezing and Beyond

Gardner, Robert: Melting, Freezing and Bioling Science Projects with Matter

Greathouse, Lisa: Melting and Freezing

Harrison, Lilian Elsom: Solubility and Freezing Point Depression Curves of Ester Water Systems

Lowe, Bella: Experimental Cookery from the Chemical and Physical Standpoint

nationalgeographic.org

rsc.org (Royal Society of Chemistry)

Rogers, Gordon FC & Mayhew, Yon R: Thermodynamic and Transport Properties of Fluids

Royston, Angela: Solids, Liquids and Gases

sciencedirect.com

ssec.si.edu (Smithsonian)

Walshaw, Keith: Gases, Liquids and Solids

This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

Comments

Brian OldWolf (author) from Troon on January 14, 2020:

Thanks Nikolas

Brian OldWolf (author) from Troon on January 14, 2020:

Thanks Nikos

nikos on January 13, 2020:

interesting information

ling on October 22, 2019:

why do some drinks freeze faster than others

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Brian OldWolf (author) from Troon on October 06, 2019:

You may ask Garth....

In some traditional sense, you could consider water an element, but it doesn't qualify as an element according to the scientific definition. An element is a substance consisting of only one type of atom. Water consists of two types of atoms: hydrogen and oxygen so it is a compound.

Garth on October 05, 2019:

May I ask how water is an element if it consists of hydrogen and oxygen?

Brian OldWolf (author) from Troon on July 04, 2019:

You're welcome Raven1211

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Brian OldWolf (author) from Troon on February 18, 2019:

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Brian OldWolf (author) from Troon on January 15, 2019:

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Liaa on January 10, 2019:

In freezing point it is often stated that vapour pressure of liquid=vapour pressure of solid

How??? Can u please answer.

Brian OldWolf (author) from Troon on January 04, 2019:

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Brian OldWolf (author) from Troon on December 10, 2018:

Thank you

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You are most welcome

C on December 04, 2018:

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Brian OldWolf (author) from Troon on November 14, 2018:

Thanks "Anonymous" always glad to see that the article is helpful... that's thanks enough