The world’s lightest material is carbon graphene aerogel, which is seven times lighter than air. Aerogels are a class of substances that are made by removing the liquid from a gel, and they are about 99.8% air, which gives it a holographic appearance. Carbon graphene aerogel is a substance made by drying out carbon gels, resulting in a substance that weighs 0.16 milligrams per cubic centimeter. The substance is able to absorb as much as 900 times its own weight, leading scientists to promote its possible use in cleaning up oil spills.
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