An element with mass number 81 contains 31.7% more neutrons as compared to protons. Assign the atomic symbol

An element with mass number 81 contains 31.7% more neutrons as compare

1.	An element with mass number 81 contains 31.7% more neutrons as compared to protons. Assign the atomic symbol
Answer» Solution :Mass NUMBER = 81, i.e., `p + N = 81` If PROTONS = x, then neutrons `= x + (31.7)/(100) XX x = 1.317 x` `:. x + 1.317 x = 81 or 2.317 x = 81 or x = (81)/(2.317) = 35` Thus, Protons = 35, i.e., ATOMIC no. = 35 Hence, the symbol is `._(35)^(81)Br`