physical change

[ fiz-i-kuhl cheynj ]

noun

, Chemistry.

1. a usually reversible change in the physical properties of a substance, as size or shape:

   Freezing a liquid is a physical change.

Word History and Origins

Origin of physical change¹

First recorded in 1750–60

Example Sentences

Every mental experience has physical causes, and physical changes in your body often have mental consequences, thanks to your predicting brain.

From Nautilus

The card’s drivers will detect cryptocurrency mining activities automatically and scale down the performance without any actual physical changes to the card itself.

From Popular-Science

The only process that exists is to add sites undergoing physical change to the List of World Heritage Sites in Danger.

From Washington Post

When you learned that my name is David, there’s a physical change in the structure of your brain.

From Nautilus

The possibilities for physical change have never been greater.

From No Straight News

The fact that she should be subjected to such scrutiny over a barely perceptible physical change is an absurd waste of media ink.

From The Daily Beast

Like his teenage counterpart, the dad-olescent is dealing with dramatic physical change, but for the worse.

From The Daily Beast

Variation itself is quite peculiar, and as far removed from any physical change as is possible to conceive.

From Project Gutenberg

Naturally there was no physical change, but in some inexplicable way she felt that an inward light was quenched.

From Project Gutenberg

Dowie had not been one of those who had seen the gradual development of the physical change in her.

From Project Gutenberg

Now red sandstone is an infallible mark of rapid deposition, and therefore of active physical change.

From Project Gutenberg

And now with horror I suddenly realized that a physical change had marched alongside the fluctuations of our temper.

From Project Gutenberg

More About Physical Change

What is a physical change?

A physical change is a change to the physical—as opposed to chemical—properties of a substance. They are usually reversible.

The physical properties of a substance include such characteristics as shape (volume and size), color, texture, flexibility, density, and mass.

Physical changes are not to be confused with chemical changes, which form whole new substances.

Physical change vs. chemical change

What do tearing paper, chopping wood, and boiling water all have in common? They’re all physical changes. Physical change is an important concept in chemistry; it describes changes to things that don’t result in brand-new substances.

Physical change upholds the molecular structure of a substance. Water, for example, is composed of two hydrogen molecules and one oxygen molecule, no matter whether it’s boiling or frozen. You can change the physical state of water (for example, going from liquid to frozen) without impacting its underlying molecular structure.

A chemical change, in contrast, does impact a substance’s molecular structure: one substance becomes another in a way that’s usually irreversible. The reaction of iron and oxygen forms a whole new substance: rust.

Dissolving salt in water is an example of a physical change. The salt crystals have changed their physical (not chemical) state, and if you evaporate the water by boiling it, the salt will recrystallize and “magically” appear in the bottom of the pot.

Physical changes are all around us. They happen when ice forms or when metals form an alloy, like bronze and stainless steel. The distinction between physical and chemical changes is also a foundational concept in chemistry.

Did you know ... ?

Can’t remember the differences in physical versus chemical change? Here’s a trick:

The initials of the phrase the very special cows meet daily stand for texture, volume, size, color, mass, and density. These are physical properties of a substance, and changes to them mark physical changes.

What are real-life examples of physical change?

The graphic shows some examples of physical changes:

<img aria-describedby="caption-attachment-141116" loading="lazy" class="wp-image-141116 size-full" src="https://www.dictionary.com/e/wp-content/uploads/2019/11/TC_608336-examples-of-physical-changes-5aa986371f4e1300371ebebb.png" alt="" width="768" height="512" srcset="https://www.dictionary.com/e/wp-content/uploads/2019/11/TC_608336-examples-of-physical-changes-5aa986371f4e1300371ebebb.png 768w, https://www.dictionary.com/e/wp-content/uploads/2019/11/TC_608336-examples-of-physical-changes-5aa986371f4e1300371ebebb-300x200.png 300w" sizes="(max-width: 768px) 100vw, 768px" />

ThoughtCo.com

2.5c @McWhorterElem @LubbockISD sanding to show a physical change pic.twitter.com/rfOAL2qkMq

— Samantha Huston (@HustonsClasses) September 12, 2019

The kids loved burning Sucrose and looking at whether it's a chemical or physical change #WeAreGR pic.twitter.com/Uc4AU3HLok

— Coach Alicia Dutch (@GRHSgirlxctrack) September 13, 2019

What other words are related to physical change?

 

• chemical change
• physical property
• chemical reaction
• composition
• atom
• molecule

Quiz yourself!

Which of the following is not a physical change?

A. Wood catching fire
B. Crumpling paper
C. Melting ice
D. Dissolving sugar in water