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How is the mass number written?

Answer 1

Avery Adams

On the top left side in an isotope...

An isotope is usually fully written in the form of:

#""_Z^AX#

where:

#Z# is the mass number

#A# is the atomic number

#X# is the element's symbol

The mass number is also written at the top of an element's position on the periodic table. It has no units, as the normal units are presumed to be atomic mass units or #"u"#.

Note that #1 \ "u"=1.66*10^-27 \ "kg"#.

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Answer 2

Axel Alvarado

The mass number is typically written as a superscript before or after the chemical symbol of an element. It represents the sum of the number of protons and neutrons in the nucleus of an atom.

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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.