The isotope of an atom containing 31 protons and 39 neutrons suddenly has two neutrons added to it. what isotope is created? look up the peridoic table to find which element has 31 protons. gallium-72 yttrium-41 yttrium-72 gallium-41

Gallium-72

Explanation:

Atomic number is defined as the number of protons or number of electrons that are present in an atom. It is characteristic of an element.

Atomic number = Number of electrons = Number of protons = 31

Thus the element with atomic number of 31 is Gallium.

Mass number is defined as the sum of number of protons and neutrons that are present in an atom.

Mass number = Number of protons + Number of neutrons

There were 39 neutrons and then 2 more were added , thus there are 39+2 = 41 neutrons

Thus mass number = 31 + 41 = 72

Thus the element will be gallium with 72 mass number.

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