noun Download 🔗Share The second lightest chemical element (symbol He) with an atomic number of 2 and atomic weight of 4.002602, a colorless, odorless and inert noble gas. Examples : "The birthday balloons were filled with helium, which made them float to the ceiling. " element chemistry substance material physics science Chat with AIVocabulary GamePractice Reading
noun Download 🔗Share A form or sample of the element. Examples : "The science experiment required a sample of helium. " element substance chemistry Chat with AIVocabulary GamePractice Reading