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Name: Cleopas
Status: Other
Grade: Other
Location: N/A
Country: N/A
Date: June 2006

Why is it that when you boil an egg, it turns hard? What properties does it have that make it do so?


Eggs are largely protein, and protein molecules tend to be long and folded up on themselves. Heating an egg, causes the protein molecules to unfold and link together with other protein molecules. Very large chains of many protein molecules result. The joining together of the individual protein molecules, into much larger ones, results in the egg becoming more solid. Other common substances such as plastics and rubber are made a similar way by causing smaller molecules that start off as liquids or even gases, to join together into large interconnected chains, resulting in solid or rubbery substances.

Robert Wilson

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