Asked Dec 4, 2019
Which of the following element has the isotope with 21 neutrons and mass number of 40?

(1) Argon
(2) Calcium
(3) Potassium
(4) Chlorine
A)The element is calcium.
B)The element is argon.
C)The element is potassium.
D)The element is chlorine.

Expert Answer

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Number of protons can be determined by subtracting number of neutrons from the mass number of an element. O...

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