One isotope of a metallic element has the mass number 67 and 37 neutrons in the nucleus. the cation derived from the isotope has 28 electrons. write the atomic symbol for this element.

Zinc: Zn

Explanation:

The mass number of element is 67

mass number = number of protons + number of neutrons

So number of protons = 67-37=30

Thus the atomic number of element is 30

the atom with atomic number 30 is zinc

On losing 2 electrons it will form dipositive ion which will have 28 electrons

The symbol of element is Zn

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