Question

Question 10 of 21 > Identify the missing information for each atom or ion. Note that the atoms and ions are not necessarily neutral. A Se ion has a mass number of 78 and a charge of 2. Determine the number of neutrons, protons, and electrons in this ion. number of neutrons: number of protons: number of electrons: An ion has a mass number of 65, 36 neutrons, and a charge of 1. Identify the element symbol, and determine the number

Answer 1

10) Atomic number (2): Atomic number gives the number of electrons present outside the nucleus or the number of protons present in the nucleus. Atomic number, Z = no of electrons (or) no of protons Mass number (A): Mass number gives the sum of number of protons and neutrons present in the nucleus Mass number, A= no of protons + no of neutrons ----------------- ------------------- -- Atomic number of selenium, Z = 34 Mass number , A = 78 No of neutronons = A-Z = 78-34 = 44 No of protons = Z = 34 Charge = -2 No of electrons = 34+2 = 36 Symbol : Sea- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 11) A potassium atom loses 1electron to form a K* ion A sulfur atom gains 2 electrons to form a 3-ion