Bar of soap 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 t

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Bar of soap 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. For images showing the expanded soap see C019/4406 and C019/4407.

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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, education, experiment, foam, formation, ivory, law, microwave, physical, school, science, sequence, soap, white