Loading practice questions
ObjectiveMcq
Print Protected
This page is protected for print. Use the website to view the content.
What is the full form of "At"?
Correct Answer: D — Astatine
Explanation:
Astatine is a chemical element with the symbol At and atomic number 85. It is the rarest naturally occurring element in the Earth's crust, occurring only as the decay product of various heavier elements. All of astatine's isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours.