Before and after of a bar of soap that has been heated in a microwave. This is a particular type of soap that has air whipped into it. This makes it f

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Before and after of a bar of soap that has been heated in a microwave. This is a particular type of soap that has air whipped into it. This makes it float in water. When heated in a microwave the water trapped inside the soap vaporizes and the trapped air expands. The soap also softens. These physical changes cause the soap to expand and form a rigid foam. Soap that does not have air whipped into it would melt in a microwave.

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Size: 4288px × 2848px
Photo credit: © CORDELIA MOLLOY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: bar, change, charles, chemical, chemistry, closed-cell, comparing, comparison, cooked, education, expanded, expansion, experiment, foam, formation, heated, ivory, law, microwave, physical, rigid, school, science, soap