Uranium-235 is used in nuclear fission. Determine the

Solution : Let’s consider the 1st set of data : The given symbol is P. Phosphorus is the chemical name of symbol P. It has an atomic number of 15. Atomic number indicates the number of protons and electrons. So there are 15 p rotons and electrons. But there is an charge of 3- which indicates there is gain of 3 electrons, Hence number of electrons here is 1 8. Mass number is given as 31. To find the number of neutrons, we subtract the number of protons from the mass number as mass number is the sum of number of protons and neutrons. Therefore, Number of neutrons = 31- 15 = 1 6. Let’s consider the 2nd set of data : Number of protons is given as 34