Question

The mass number of iodine is 126, and it’s in the 53rd place in the periodic table. It has ___ protons and ___ neutrons

Answer 1

Answer;

53 protons

73 neutrons

The mass number of iodine is 126, and it’s in the 53rd place in the periodic table. It has 73 protons and 53 neutrons.

Explanation;

• The mass number of an element is the sum of the number of protons and the number of neutrons in the nucleus of an atom of the element.
• Therefore, the mass number of Iodine is 126, which means the sum of its protons and neutrons is 126.
• Atomic number of an atom on the other hand is the number of protons in the nucleus of the atom. The atomic number of Iodine is 53 , which means its nucleus has 53 protons.
• Thus, to get the number of neutrons we subtract the atomic number from the mass number, which will be 73 neutrons.

Answer 2

It has 53 protons and 73 neutrons.

(Neutrons: 126-53 = 73)

:)