Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Cold Water and Stain Removal
Name: Nick K.
Status: student
Age: 12
Location: N/A
Country: N/A
Date: 9/22/2003


Question:
How does cold water remove stains?


Replies:
Nick,

Stain removal is a matter of dissolving (loosening) the stain and then washing it off the fabric. Cold water serves as the solvent and it works much better if it is warm rather than cold. In warm water, the molecules are rattling around faster than they would be if the water was cold. Faster moving molecules are better at knocking the stain material off the fabric's fibers because (just like a moving baseball) the faster they move, the harder they hit.

The whole process can be made even more effective if one uses a suitable soap or detergent to assist the removal. Soaps and/or detergents are able to assist the loosening process and also they are able to suspend the stain material so that it cannot be re-deposited on the fabric.

A word of caution: Some stains can be "set" in the fabric and made harder to remove if hot water is used because hot water may cause a chemical reaction to occur that binds the stain and its reaction products to the fabric.

Regards,
ProfHoff 728


Water is a good solvent for a wide range of substances that might stain a fabric. Very roughly speaking this solubility is independent of the temperature. However, hot water can promote other chemical reactions between the staining substance and the fabric that causes the staining substance to chemically bond to the fabric and so makes it more difficult to remove. This is only a partial answer to a very complex process -- the staining of various fabrics.

Vince Calder


Cold water does not remove stains; it merely permits the stain removing agents to work before the stain is set by heat. Heat, such as in the form of hot water, will cause the stain to set, and it may become permanent. Most processes for dying cloth or yarn use heat to set the dyes, to cause them to bond permanently. A chemist can probably explain why heat does this.

Korah Erbacher



Click here to return to the General Topics Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory