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What is the largest monoatomic anion? Is it #"Bi"^(3-)#?

Answer 1

Henry Antrim

The largest known monatomic ion is probably #"At"^"-"#.

Bismuth

Bismuth is a metal. It tends to form cations, not anions.

If #"Bi"^"3-"# exists, I can't find its ionic radius.

Polonium

Polonium is a metalloid. Its most common compounds are polonides.

Compounds like #"Na"_2"Po"# and #"BaPo"# contain the #"Po"^"2-"# ion.

Its largest calculated radius is 225 pm.

Astatine

We would expect the ionic radius of #"At"^"-"# to be less than that of #"Po"^"2-"#.

However, its ionic radius is 227 pm.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.