53
53 + 25 = 78
78 multiplied by 53 is 4,134.
131
B. 53 neutrons. The number of neutrons in an atom is calculated by subtracting the number of protons from the atomic mass of the isotope. Since Iodine-131 has an atomic mass of approximately 131, and it has 53 protons, the number of neutrons is 131 - 53 = 78.
Iodine is element number 53 and and so has 53 protons. There are thus 131-53 = 78 neutrons
78/1.06 = 7800/106 = 3900/53
The atomic number of iodine, or I, is 53. Thus, neutral iodine would have 53 protons and 53 electrons. However, since we're talking about I-, we need to add an additional electron to this number, making it 54. Finally, the specific isotope of iodine in question, 131I, has 131 - 53 = 78 neutrons.
the solution to the equation -53 plus 1 -26 is -78.
134
78
78