An isotope of iodine is I-126.how many protons, neutrons &electrons does it have
126 is the total of protons and neutrons. For the number of protons, you should look up the atomic number of iodine. It is 53. The number of electrons is the same.
Subtract 53 from 126 for the number of neutrons.
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To determine the number of protons, neutrons, and electrons in an atom, we look at its atomic number, mass number, and charge.
For the isotope I-126:
1. Protons: The number of protons is equal to the atomic number of the element. In this case, iodine (I) has an atomic number of 53. Therefore, I-126 will also have 53 protons.
2. Electrons: For a neutral atom, the number of electrons is equal to the number of protons. Since the isotope I-126 has 53 protons, it will also have 53 electrons.
3. Neutrons: The mass number of an isotope represents the total number of protons and neutrons in the atom. In this case, the mass number of I-126 is 126. Since we know there are 53 protons (from the atomic number), we can calculate the number of neutrons by subtracting the atomic number from the mass number:
Number of neutrons = Mass number - Atomic number
Number of neutrons = 126 - 53
Number of neutrons = 73.
So, the isotope I-126 has 53 protons, 73 neutrons, and 53 electrons.