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3 votes
How many neutrons make up one of these potassium atoms?

19
20
38
58

User Wierzbiks
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2 Answers

1 vote
b 20
( i took the test)
User Frank Wiles
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4 votes
To find the number of neutrons you take the atomic mass, 39, and subtract the number of protons, 19.
so 39-19=20
potassium has 20 neutrons
User Sahir
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