Answer:
A chemical element is a substance that contains only one type of atom. If a substance contains more than one type of atom, it is a compound. An element can be a solid, liquid or gas. The smallest particle of such an element is an atom.
Explanation:
uhm Confidence
answer is b
use pv=nRT
p directly proportional to moles(n)
p1/p2=n1/n2
p/p2=n/2n
p2=2p
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