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Name:  Joe W.
Status: student
Grade: 9-12
Country: N/A
Date: 5/9/2005

How do you find neutrons in a Isotope?

The usual way is to measure the atomic weight of the element. The number of protons determines the chemical nature of the element. There are a number ways to measure the atomic weight, the most accurate being mass spectrometry, which separates atoms according to their mass number (more precisely mass / charge ratio (m/e)). The difference is the number of neutrons present in the nucleus.

Vince Calder

Joe - subtract atomic number from atomic weight.

The atomic weight of the isotope is the number of protons plus neutrons. The atomic number is the number of protons, period.

So [atomic weight] - [atomic number] = [number of neutrons]

Jim Swenson

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